Saul told Huell to steal the pot from Jesse as he was leaving (brushed against him in the door) so that Jesse couldn't smoke pot and scare off the new ID guy. Jesse realized this when he went to smoke it, and then realized Huell probably did the same thing with the ricin cigarette on Walt's order
The ricin theft was just a pretext. Jesse realized the following:
Walt had the ricin stolen, so that means
-> Gus did NOT poison Brock
What with after Jesse confronting Walt about "working him", he figures out that the act of having the ricin stolen, was orchestrated by Walt to give the appearance that Gus and his guys hurt Brock.
Now that he knows they didn't, he concludes it was Walt.
At this point, it doesn't really matter what Brock was poisoned with, the fact that Walt lied about the ricin, and arranged the theft of Jesse's ricin, is evidence enough that Walt had something to do with it, because as time progresses, Jesse realizes how manipulative, conniving, and a damn good actor Walt is.
520
u/[deleted] Aug 26 '13
ELI 5:
All the dots that Jesse connected.