September asks if Michael showed anything else, and Walter says he did: "There is one thing I haven't told the others. He showed me that, for the plan to work, I would have to sacrifice myself." Walter asks September if that's right, and September, after a moment, says it is, and asks Walter if he's frightened. Walter said he'd be lying if he said he wasn't.
Then he asks if September thinks Michael showed him all these other experiences so that he knew that he has loved and had incredible moments and connections: "Because it will make it easier for me to come to terms with what I have to do? You think that's why he did it?" September says he doesn't know, but gently asks Walter if he remembers that it was Walter's own idea to sacrifice himself for the plan. This appears to come as some news to Walter. "You said you had caused so much unintended damage, you felt this was your chance to make amends," says September, and Walter sadly nods.
But hey, as long as we're revisiting -- and revising -- memories, September asks Walter if he remembers getting a white tulip. "Remember? We did a whole episode about it!" says Walter.
Turns out it wasn't a sign from god, as much as it was -- as September pulls a briefcase from a hidden compartment underneath a record player, much like in "A Short Story About Love," he says the white tulip was important. "I took it from the other timeline, and kept it," he says, opening the briefcase and explaining to Walter that when they devised the plan to stop the invasion, Walter didn't think they could succeed, but September knew the tulip would give him strength, just as it did before.
He shows Walter the envelope that contained the drawing of the white tulip, all those years ago. Walter's face lights up, but he's crestfallen to find that the envelope is now empty. "I could use that tulip right now," he says, and September says he doesn't know what Walter did with it; only Walter would know that. So September is arguably shaking Walter's faith in God and he got Walter worked up about the tulip only to disappoint him? Good morale boost there, September.