I turned to lennie and said jump, and he jumps. He Couldn't swim a single stroke. He nearly drowned before we could get him. And he was so dang nice to me for pulled him out. Clean forgot I told him to jump in. Well, I haven't done nothing like that no more."
Step-by-step explanation:
Basically he saved his life after nearly drowning him in a river and felt bad, so never did it again. This has been modified from the original.