פירוש על קידושין 117:4

Rabin is ironically called “pious” even though his actions don’t seem all that pious. He is supposed to betroth a woman for his son, but then decides he’s going to betroth her for himself. The Talmud asks how Rabin could do such a thing. His excuse is that the men giving the woman away in betrothal (the brother, the father?) did not want to give her to the son, they wanted the father. And he was afraid that if he went back to his son and told him about what was happening, the girl would meanwhile be given to another.
Sounds like a good story to me.