Notes from a talk delivered at LeakyCon in Boston, MA, USA, on Sunday, October 13, 2019.  Posted by request.

Thank you for coming to think about what is, to me, the most difficult relationship to understand in Harry Potter.  There are things about Snape and Dumbledore that I’ve been trying to figure out since July 2007 and I’m still trying to get there.  I see the author’s perspective on this relationship changing, too, as she grows older. When she wrote Deathly Hallows, she was close to Snape’s age of 38 and she wrote Dumbledore as almost godlike.  In the Fantastic Beasts series, she writes Dumbledore as younger than she is now.

In 2016, Rowling wrote that McGonagall added Snape’s portrait to the headmistress’s office after a conversation with Harry.  When I picture that portrait gallery, Snape makes for an arresting addition: the very young protégé hand-selected by the legendary Albus Dumbledore to see Hogwarts through one grim, pivotal year in its history.  I wonder where she put his portrait. Is it next to Dumbledore’s, behind her desk? I wonder how these two portraits interact.

As we learn more about Dumbledore’s backstory, we see how he could be sure Snape’s repentance was real:  because Dumbledore recognized it from his own experience of facing his evil and renouncing it. This is a story that’s become especially urgent in the current political climate, something we can see being emphasized in the Fantastic Beasts films that were released in 2016 and 2018.  Considering that Dumbledore and Snape are both essentially reformed white supremacists who used their knowledge of evil to fight Dark Magic in ways not available to those who have always been pure of heart, I think their stories are worth considering now in a way that wasn’t as topical in the years when Obama was president and Godwin’s Law was still in place.

Dumbledore made significant bequests to Harry, Ron, and Hermione:  a Snitch, a Deluminator, a first edition, the sword of Gryffindor. In a similar spirit, he also left things to Snape:  the Headmaster job, the final message for Harry, and the Elder Wand, though that didn’t work out the way he intended. He left Snape the responsibility for everyone at Hogwarts, a powerful cover story that was years in the making, the private sanctum of the Headmaster’s office, and his personal gratitude for doing whatever it took to agree to kill Dumbledore and then survive a terrifying time without his mentor.

Rowling wrote such complexity into the Dumbledore-Snape relationship that we can see several different interpretations of their dynamic, including one that Snape believed for a time, before Dumbledore died:  that Dumbledore used Snape as a pawn. For a long time, I had difficulty believing that Snape could possibly have drawn strength from the memory of Dumbledore in his final year.  But that is what I think now, and I’ll go through why I think so, starting with the headmaster’s password.

Harry took Snape’s memories to the headmaster’s office and said, “Dumbledore!” without thinking, and the gargoyle let him through.  Until then, Harry and Snape had one shared password of sorts: Lily. When Harry saw Snape’s Patronus, without even knowing whose it was, it felt deeply familiar to him:  both Harry and Snape had been formed by love of the same person. We’ve just seen Harry spend a year struggling to work from Dumbledore’s instructions, sometimes losing faith.  The second shared password points us to the possibility that Snape has been going through the same struggles during the same year, in parallel. 

Remember how Harry raged against Dumbledore in Deathly Hallows?  Snape would have understood the feeling:

“Look what he asked from me, Hermione! Risk your life, Harry! And again! And again! And don’t expect me to explain everything, just trust me blindly, trust that I know what I’m doing, trust me even though I don’t trust you! Never the whole truth! Never!”

Remember Snape telling Dumbledore he might change his mind about killing him? “You refuse to tell me everything, yet you expect that small service of me!”  Dumbledore says, “You gave me your word, Severus.”

He was just as inexorable when Harry asked him in the cave, desperately, “Why can’t I drink the potion instead?”

“Because I am much older, much cleverer, and much less valuable,” said Dumbledore.  “Once and for all, Harry, do I have your word that you will do all in your power to make me keep drinking?”

For both Harry and Snape, when they keep their word to Dumbledore, what they get in return is Dumbledore’s gratitude that they have made him feel less alone, a rare experience for the most powerful wizard of the century at the end of his life.  When Dumbledore was weak from the poison in the cave, he said, “I am not worried, Harry. I am with you.” When Snape saved Dumbledore’s life from the curse in the ring, he said, “I am fortunate, extremely fortunate, that I have you, Severus.”

He asked them to help him in his weakest moments, called for them specifically to be with him through mortal peril and at his death, and they saw that this brought him comfort.  Dumbledore, asking for help for himself. They might have doubted his guidance in their own lives, but where Dumbledore’s needs were concerned, I have to think Harry and Snape must have realized, in time, that this meant Dumbledore loved them.

When Harry meets posthumous Dumbledore at King’s Cross, we see someone at peace:  “Happiness seemed to radiate from Dumbledore like light, like fire:  Harry had never seen the man so utterly, so palpably content.” Dumbledore mentions Voldemort’s obsession with the Elder Wand and says, “Poor Severus,” as though saddened but not self-recriminating, the way he sounds about Grindelwald or Ariana or Sirius.  At least in Harry’s vision, Dumbledore is content with how things have played out. How can he be content when the battle is still going on, Voldemort has not been defeated, and Harry has not yet made a choice to return and finish him off? The Dumbledore of Harry’s vision assures Harry that it’s up to him what to do next; there are no more directives from him.  This tells me something important about Dumbledore:

He cared more about keeping souls whole than winning the war.  It’s possible to read him as wanting to win the war against Voldemort above all things, and manipulating everyone ruthlessly into serving his plan, even if it meant deceiving them about their own lives.  But to me, this reading doesn’t seem right.

I remember feeling aghast, much as Harry did, when I first read in Half-Blood Prince that Dumbledore wanted Harry to agree to follow orders such as force-feeding him poison or saving himself and leaving Dumbledore to die.  I was appalled when Dumbledore said things like “Your blood is worth more than mine.” What? But Dumbledore is consistent in believing that only Harry is essential to win against Voldemort — not himself, not Snape.  It’s Harry’s fight, and his own job as a teacher is to do his flawed best to prepare Harry to fight it.

That goal can’t be dependent on a guaranteed victory in war.  Nobody can control that, especially when planning past their own deaths.  But Dumbledore can put all of his formidable teacher gifts toward guiding his students to take care of their souls.  It looks to me like he wanted that more than he wanted to impose his own posthumous agenda. This is the man who literally told Harry and Snape to kill him and make their own way! 

The contented Dumbledore of King’s Cross said, “Your soul is whole, and completely your own, Harry.”  In Rowling’s universe, as Hermione explains helpfully, “Look, if I picked up a sword right now, Ron, and ran you through with it, I wouldn’t damage your soul at all.”  And the story of Dumbledore’s relationship with Snape is defined by the question:

“And my soul, Dumbledore?  Mine?”

Dumbledore and Snape have two different conversations about Snape’s soul.  The first begins with the not-entirely-reassuring words, “You alone know whether it will harm your soul” to kill Dumbledore.  That’s true, and it’s exactly what they need to consider, but this answer is not comforting. 

Much of “The Prince’s Tale” documents how Dumbledore tried to nudge Snape toward feeling remorse for the sake of his own soul.  It didn’t take. Year after year, whenever he checked to see if Snape could be honest about remorse for the life he had given Lily Potter’s child, the answer was no – Snape persisted in groundless bias, lying to himself that Harry was spoiled or craved notoriety to distract himself from the unbearable guilt of acknowledging that his long-ago hate crimes had led to Harry’s life as an abused orphan who is the number one target of a mass murderer.  As Hermione said, the pain of remorse can destroy you.

But when Dumbledore needed Snape to kill him, he hit upon the key for getting Snape to care for his own soul:  get Snape to do it for Dumbledore, not for his own sake.  We know that killing someone splits the soul and remorse is the only way to become whole again.  At first, Dumbledore tells Snape to kill him to spare Draco’s soul.  This makes it sound suspiciously like Dumbledore doesn’t think Snape’s soul matters as much.  The bravest man that Harry ever knew has the guts to ask what I think might be one of life’s hardest questions:  What about me?

The answer turns out to be unsparing, which is how we know it’s the right answer for Snape:  “You alone know whether it will harm your soul to help an old man avoid pain and humiliation.”  Dumbledore brings up extremely plausible scenarios of what might happen if Death Eaters got their hands on him.  He’s rightly afraid.

So Snape is going to have to reintegrate his soul through remorse, the one thing that’s always been too difficult for him.

While Snape thinks about it, Dumbledore’s “blue eyes pierced Snape as they had frequently pierced Harry, as though the soul they discussed was visible to him.”  That’s a “look at me” moment. Dumbledore asks if Snape will be able to save his death, and the answer depends on both men seeing this tightly Occluded man for his truest self.

We humans can’t always take care of ourselves for our own sakes; it sometimes takes more than we have.  But we can do more than we thought possible when it’s to help someone else, if love is there.  This is not a bug; it’s a feature.  This is what makes love a powerful force.

That first conversation about Snape’s soul takes place after Dumbledore hurt his hand at the beginning of his last summer.  The second time is the following March, and Dumbledore’s answer shows character development that changes the story for me, and I think for them.

Snape asks Dumbledore, painfully, why he tells Harry secrets that he won’t entrust to Snape, and Dumbledore tries to explain that it’s not a matter of trust.  He can’t tell Snape he’s worried that Voldemort will kill him if he sees, through Legilimency, that Snape has learned about Horcruxes.  He misses the vulnerable jealousy in Snape’s question. Dumbledore is trying to get Snape to understand, instead, that Harry is a safer recipient for secrets because Voldemort will never possess Harry’s mind again:  “Lord Voldemort’s soul, maimed as it is, cannot bear close contact with a soul like Harry’s. Like a tongue on frozen steel, like flesh in flame —”

Is Dumbledore waxing poetic to Snape about the purity of Harry’s soul, again?  He is! Snape, with his world-class Occlumency, tries to get them back on track.

“Souls? We were talking of minds!”

Dumbledore does not take the hint.  He continues:

“In the case of Harry and Lord Voldemort, to speak of one is to speak of the other.  After you have killed me, Severus —“

Snape can’t take it anymore.

“You refuse to tell me everything, yet you expect that small service of me!” snarled Snape, and real anger flared in the thin face now. “You take a great deal for granted, Dumbledore! Perhaps I have changed my mind!”

It finally gets through to Dumbledore, who has been understandably preoccupied.  Snape knows Dumbledore loves pure Harry Potter; he’s asking if Dumbledore has come to love him, too, after Snape has given half his life to faithful service, putting himself in mortal danger for Dumbledore and pulling off feats of spycraft that no one else could.  You can’t plan to split your soul for someone and put yourself back together, alone, without love.

Dumbledore tells Snape to come to his office at the eleventh hour and reveals what he can about the final message to Harry, protecting Snape’s life by closing his eyes tightly while explaining anything that has to do with Horcruxes.  Snape is horrified and accuses Dumbledore of using him and Harry. Dumbledore finds this touching and asks if Snape has grown to care for Harry, and we know the complicated “no” Snape gives in reply:

“For him?  Expecto Patronum!”

Dumbledore watches the silver doe fly out his window and his eyes fill with tears, after all this time.  There’s an immediate interpretation, one that’s never fully satisfied me: that Dumbledore is moved to see Snape’s devotion to Lily’s memory.  But there’s an additional one that resonates more for me, and I understand how this one would move Dumbledore to tears.

Snape had said to Dumbledore, “I thought…all these years…that we were protecting him for her.  For Lily.”

We.

All these years.

Dumbledore once tethered Snape to life with the words, “If you loved Lily Evans, if you truly loved her, then your way forward is clear.  Help me protect Lily’s son.”

It misses the mark, for me, to think that Snape’s demonstration of his doe Patronus indicated only a devotion to Lily’s memory.  I think there’s another answer right in front of us.  Snape once thought his life was worthless and finished, but Dumbledore saw a reason to offer him a second chance at life, if he had really loved Lily and could be guided by that love.  Snape accepted the offer because Dumbledore thought he might have something good left to give, something Snape didn’t see in himself at that time.

To point out the obvious:  Lily is dead. She’s at peace.  There’s nothing new for Snape there.  Dumbledore is the one who has been the inspiration for the second half of Snape’s life, engaging him with life-or-death work that challenges even this intensely gifted man.  This is a charged moment between Snape and Dumbledore. All the dangerous things Snape has done have not been because he has grown to care for the boy, but because he took Dumbledore’s directive to heart and still lives by it, as he demonstrates to Dumbledore with the sight of his luminous Patronus.  Of course Snape wants his extraordinary mentor to look at his soul, see its wholeness, and acknowledge that after all this time, Snape was worth a second chance.

When Harry once said he told Scrimgeour that he’s “Dumbledore’s man, through and through,” Dumbledore’s eyes watered and he could not speak, and Fawkes “let out a low, soft, musical cry.”  I think this exchange between Snape and Dumbledore, too, is a moment when Dumbledore learns that his life’s work of caring for his students’ souls has been worthwhile, despite his very many shortcomings.

Those are two of the three readings that led me to believe that the memory of Dumbledore empowered Snape in his last year:  Snape keeping his soul intact for Dumbledore’s sake rather than for his own, and Snape’s Patronus attesting to his love for Dumbledore as well as Lily.  The third comes during Snape’s memory of the long-lost second page of Lily’s letter, during the wrenching scene when he reintegrates his soul with remorse, leaving a trail for Harry in Sirius Black’s bedroom.

could ever have been friends with Gellert Grindelwald.  I think her mind’s going, personally! Lots of love, Lily.

I thought for years that Lily’s love was the only important thing on that page.

Then I realized that this letter was the first time Snape learned that Dumbledore, whose soul seemed surely more pure than Snape’s ugly, Dark-Marked soul, had once been Grindelwald’s friend.

Every crisis of faith that Harry goes through in Deathly Hallows regarding Dumbledore, Snape went through, too, during the same relentless year.  Harry felt growing fear at Rita Skeeter’s hints that Dumbledore “dabbled in the Dark Arts himself as a youth,” then shock as he read Skeeter’s biography and the incontrovertible proof, in Dumbledore’s own hand, that he had once been Grindelwald’s partner, ardent and fully invested, in plotting fascism.

Snape went through those realizations, too, at the same time.

The news about Dumbledore’s past, his former fascism and the death of Ariana, changed Snape’s perception of Dumbledore in a way that would have made Snape feel less alone, not more.

This put several things about Dumbledore in a different light where Snape was concerned.  His testimony to the Wizengamot that Snape “is now no more a Death Eater than I am.” His unwavering conviction, in the face of skepticism, that Snape’s change of heart was genuine and not an act.  His insistence on Snape, and no one else, to counter Dark Magic at Hogwarts: he recognized Snape as someone who understood how to fight Dark Magic because he knew what it took to cast it and he knew the greater power of wanting to reverse it.

So the times that Dumbledore had annoyed Snape by idealizing Harry Potter as pure of heart, he was comparing Harry favorably not to Snape but to himself.  We readers knew this, but Snape, always jealous of Dumbledore’s regard, had not, until he learned of Dumbledore’s past.

It made sense, too, of one of Snape’s least favorite parts of the cover story that Dumbledore invented for him as a double agent:  that he could not be trusted to teach Defense Against the Dark Arts because he might be tempted back to his old ways. There’s no evidence that Snape felt the slightest pull toward Dark Magic once he pledged himself to Dumbledore.  When Umbridge asked Snape, “Do you have any idea why Dumbledore has consistently refused to appoint you?” he could not bring himself to mouth the lie, managing only to say, “I suggest you ask him.” But we saw in Crimes of Grindelwald where Dumbledore might have gotten the idea for this cover story.  He was once removed from the Defense post and knew, because he still saw Grindelwald in the Mirror of Erised, that he couldn’t be trusted with Dark Magic. 

Most of all, Snape’s understanding of Dumbledore’s guilt about his past gave new significance to the harshest words that Dumbledore speaks to anybody:  “You disgust me.” Dumbledore’s judgement of Snape, who sees nothing wrong with begging for Lily’s life in exchange for the lives of her husband and child, comes not from moral superiority but from recognition. 

Snape was an effective mentor for Draco because they both knew:  there was nothing disgusting Draco could do that Snape had not already done.  Snape was able to maintain that connection, that trust, by signaling: I know what you’ve done, and I am still here.

Knowing that Dumbledore, too, had once seen nothing wrong with letting people die for what he wanted would have given Snape a different understanding of the harsh words, “You disgust me.”  Dumbledore shared not only Snape’s self-loathing but his unresolved shame, and he remained close to Snape to the end of his life. 

Throughout the year that Snape was Headmaster, he kept the half of the letter that said Dumbledore had once been friends with Grindelwald.  It was evidence that the mentor who believed that Snape had it in him to revert all the way back to Dark Magic without harming his soul knew firsthand how much he was asking of Snape – knew it could be done and knew, from his own life, what kind of person a former fascist could become. 

The lesson of the Snape-Dumbledore relationship is learning how to make that happen.  Only someone who has managed this sort of change, someone who has the means to overpower others but knows not to attack, not to dominate, has the greatness to command the allegiance of the Elder Wand from Dumbledore.  This is the qualification that Dumbledore had in mind when he planned to pass the Elder Wand to Snape, what Grindelwald meant when he told Voldemort that the wand would never be his, and what Draco and Harry, who learned Expelliarmus from Snape, proved to have within them.

Voldemort kills Snape for possession of the Elder Wand.  That’s not how it was supposed to go. In King’s Cross, Harry asks:

“If you planned your death with Snape, you meant him to end up with the Elder Wand, didn’t you?”

“I admit that was my intention,” said Dumbledore, “but it did not work as I intended, did it?”

“No,” said Harry. “That bit didn’t work out.”

What did Dumbledore hope would happen, then? We know that in the Final Battle, when Harry and Voldemort cast Expelliarmus and Avada Kedavra at each other, the Elder Wand goes “spinning through the air toward the master it would not kill.” Dumbledore wanted the Elder Wand to recognize the mercy and protectiveness in Snape’s Killing Curse and transfer allegiance to Snape, quietly, without Snape having to lay a hand on it.  He expected Voldemort might violate his tomb and take the wand, but he had hoped that any spell Voldemort cast against Snape with it would fail because the Elder Wand would not kill its master.

Dumbledore also knew he could trust Snape to be the rightful owner of the Elder Wand because with all powerful magical objects, Snape handles them without greed, not for personal gain but to protect others. In his third year, Harry saw that his Invisibility Cloak, one of the Deathly Hallows, worked perfectly for Snape because Snape was using it in the belief that he would protect children from murderers. Dumbledore, in contrast, says he once borrowed the Cloak from Harry’s father “out of vain curiosity, and so it could never have worked for me as it works for you, its true owner.” The sword of Gryffindor cannot be owned but presents itself of its own volition to worthy Gryffindors, yet it permitted Snape to handle it. 

Dumbledore planned not to tell Snape about the Elder Wand for two reasons: it wouldn’t be safe and it wouldn’t be necessary. He didn’t want Voldemort to learn of Snape’s ownership through Legilimency and kill him. He also knew Snape would be a worthy owner, a Master of Death, whether or not he was conscious of owning a Deathly Hallow. In the “King’s Cross” chapter, the Dumbledore in Harry’s vision says he has found that “perhaps those who are best suited to power are those who have never sought it.”

But the flaw in the plan was that Dumbledore didn’t foresee Draco casting Expelliarmus, choosing the defensive spell Snape ingrained into him rather than the violence his father or Voldemort had groomed him to use.  Dumbledore had never been able to turn either Tom Riddle or Snape away from Dark Magic when they were students, but he lived long enough to see that Snape’s teaching reached Draco.

We can’t go back in time, but if we get a second chance, we can learn from the past and do better.  Dumbledore and Snape had their own history, reaching back to Dumbledore’s mishandling of the murder attempt on Snape as a student, but together, they did better for Draco and Harry.

There’s no way to know what might have happened if Dumbledore had had a mentor’s guidance when he met Grindelwald, or if Dumbledore had reached out to Snape when he was nearly killed rather than compounding his trauma by swearing him to silence and letting the Marauders go unpunished.  It’s not that anyone owed them such connections in order to prevent them from joining fascists – neither of them had any business joining hate movements anyway. But the lack of such connections didn’t help. Twenty years, a hundred years later, both Dumbledore and Snape tried to learn from their mistakes for Draco and Harry. 

Dumbledore’s gag order about the Marauders’ Prank contributed to the estrangement between Snape and Lily.  When Snape tried to warn her against the Marauders, she said, “You’re being really ungrateful. I heard what happened the other night.  You went sneaking down that tunnel by the Whomping Willow, and James Potter saved you from whatever’s down there –” That must have been galling for Snape, to be unable to defend himself and explain what had really happened.  But he kept his word to Dumbledore.

We see Dumbledore doing better for Harry at the beginning of sixth year, surprising him with the advice to tell Ron and Hermione about the contents of the prophecy:  “I think they ought to know. You do them a disservice by not confiding something this important to them. You need your friends, Harry.”

Dumbledore also learned from the “fiasco” of assigning Snape to teach Harry Occlumency instead of doing it himself.  There has to be mutual trust. The hostility between Snape and Harry doomed the lessons and Sirius died for it. The following school year, after Draco took the Dark Mark, Dumbledore charged Snape with keeping an eye on him instead of trying to do it himself.

When Draco nearly died from Sectumsempra, Snape enacted what he had learned from the mishandling of his own near-death.  He healed Draco immediately, “told the staff precisely what had happened,” commanded Harry to hand over his spellbook, and assigned Harry heavy detentions, with McGonagall’s full backing.  His quick action prevented Draco’s wounds from scarring and did something equivalent for Harry. Snape dragged the truth about the spellbook out of Harry, even if Harry denied it and hid the book itself.  It was no longer Harry’s uneasy secret, and as a result, it wouldn’t fester and cause him guilt, the way Slughorn’s secret memory of the Horcrux conversation tormented him. The severe detentions drove home the gravity of what had almost happened, but more importantly, they allowed Harry to serve his penalties and then walk free, lesson learned, with gratitude for the close call.  As Dumbledore said to Ginny at the end of Chamber of Secrets, “There has been no lasting harm done.” 

Through the openness of his actions, Snape turned Harry’s heedless use of Dark Magic into something Forgivable, forgiven.  Snape took the shame out of it for Harry and laid on the accountability. Harry and Draco were still underage at that point, by weeks, and Snape was an adult who took care of them.

Regret and accountability were part of the spell that Snape sang to heal Draco’s wounds.  Only someone who had cast this Dark Magic spell in the past and then regretted it would know how to heal it, and Snape’s magic had the extra power of his grief that his own long-ago inventions were still causing harm, hurting this child whom he had sworn to protect.  Draco has been pushing Snape away all year, yet when he was in danger, Snape’s protective response was absolute: I came as soon as I could.  I’ve got you. I’m here.  It’s in Snape’s nature to be where he’s needed, but in this case, Draco knows that this protection was doubly assured by his mother’s love. 

Snape agreed to Narcissa’s Unbreakable Vow.  He believed Draco was worth dying for, even after knowing every disgusting thing Draco had done as a Death Eater.  He reversed the curse wounds and Draco experienced that magic reversal in his very blood. Snape is the only other person at Hogwarts who can pass through the barrier that requires a Dark Mark and he can take Draco back out with him again.

There was no way that Dumbledore and Snape could have guaranteed that Snape watching over Draco would have the slightest effect.  But with the life debt to Snape in his blood, the first moment in a year that Draco had experienced healing rather than the mounting terror of Voldemort toying with him, Draco breached Dumbledore’s tower with Expelliarmus rather than attack so they could talk, in case Draco heard any cause for hope there other than killing Dumbledore. 

Dumbledore’s plan for the Elder Wand was for ownership to pass untouched to whoever defeated Dumbledore with magic intended to protect others rather than to harm, the only kind of magic powerful enough to command the Elder Wand’s allegiance.  He didn’t foresee that their care for Draco would work so well that given the option, Draco would choose disarmament and confession and hope for a second chance. That Draco did so is a gift to his teachers, whether or not he would eventually go on to renounce Dark Magic.

Draco’s Expelliarmus gave Dumbledore a moment to immobilize Harry so he could invisibly witness the exchange.  Harry saw Draco lower his wand and for the first time, mixed in with despising Draco, he gained a drop of pity that strengthened his understanding of his enemy.  Dumbledore made that happen before he died.

When Harry was about to die, he summoned the memories of his parents, Sirius, and Remus to strengthen him.  When Snape was about to die, he drew strength from thinking of Dumbledore.

In the Shrieking Shack, Voldemort tells Snape that he has violated Dumbledore’s tomb and stolen the Elder Wand.  In reaction, “Snape’s face was like a death mask. It was marble white and so still that when he spoke, it was a shock to see that anyone lived behind the blank eyes.”

With the words “death mask” and “marble white,” Rowling is calling back to the image of Dumbledore in his white marble tomb.  The blankness of Snape’s face shows that he is Occluding Voldemort as hard as he has ever Occluded in his life, hiding his reaction to the news of this desecration.  Together, I think these things show that Snape is grieving for his friend. As we learned from Harry, grief can Occlude: “Just as Voldemort had not been able to possess Harry while Harry was consumed with grief for Sirius, so his thoughts could not penetrate Harry now, while he mourned Dobby. Grief, it seemed, drove Voldemort out . . . though Dumbledore, of course, would have said that it was love. . . .”

Snape kept himself alive until Harry arrived, ensuring that Harry would be the last thing he ever saw.  Dumbledore did the same thing, keeping himself alive until Snape arrived so that Snape could be the last thing he saw.  Dumbledore didn’t want to die looking at Bellatrix or Fenrir Greyback or frightened little Draco Malfoy. He wanted to look into the eyes of someone who would take care of him and look after everything he worried about, so he could rest in peace.  He asked Snape to be the most important person in his death. Snape agreed, and he kept his word.

I find it moving to imagine their portraits next to each other.  I like to think about their mutual respect, and awe, and gratitude.  I think they would bicker, too, and be sarcastic the way they only ever were with each other.  I like to think of McGonagall working with their portraits behind her, making her even more intimidating.  I think she enjoys their company, silences them when she has to, and she knows, at last, that they’d both always deserved her trust.