And we are (thus) taught that he rebuked them only close to his death. From whom did he learn this? From Jacob, who rebuked his sons only close to his death, as it is written (Bereshith 49:1-3) "And Jacob called to his sons and said: Gather together and I will reveal to you what will happen to you in the end of days … Reuven, you are my first-born, etc." He said to him: My son, I will tell you why I did not rebuke you all these years: It is so that you would not leave me and go and cleave to Esav, my brother.
And because of four things a man should rebuke another only close to his death: So that he not rebuke him repeatedly, so that the other not be shamed in his sight, so that he (the rebuker) not bear a grudge in his heart (for his rebuke not being heeded), and so that he (the rebuked) not leave him and go (elsewhere).