"[at Don Tommasino's funeral] Goodbye, my old friend. You could have lived a little longer; I could be closer to my dream. You were so loved, Don Tommasino. Why was I so feared, and you so loved? What was it? I was no less honorable. I wanted to do good. What betrayed me? Was it my mind? My heart? Why do I condemn myself so? I swear on the lives of my children: Give me a chance to redeem myself, and I will sin no more."
January 1, 1970
https://en.wikiquote.org/wiki/The_Godfather_Part_III