You see, when Dale Cooper acts as a psychopomp and ushers Leeland’s soul over to the other side, he in effect shows that his paradigm now reaches beyond death. He therefore becomes Jesus and can now soothe with a word.
Unfortunately, this also validates Bob’s existence within Cooper’s paradigm and make him susceptible to his power. Cooper thus sets up a negative feedback loop that forces him to take Bob into his godhood and try to control him. Whoa be it to the demiurge who tries to control Satan.