After Tommasino was killed, Michael vowed to sin no more. After that, he handed control of the Corleone family to Vincent.

At the opera, Vincent bids farewell to Mary:

"Don't look at your father, it's not your father's decision, it's mine. Don't hate your father. There are things I'm going to be part of, you can't be around. After tonight, you won't see me anymore."