John Calvin Commentary Genesis 50:21

"Now therefore fear ye not: I will nourish you, and your little ones. And he comforted them, and spake kindly unto them." — Genesis 50:21 (ASV)

I will nourish you. It was a sign of a solid and not a feigned reconciliation, not only to abstain from malice and injury, but also to overcome evil with good, as Paul teaches (Romans 12:21). And truly, he who fails in his duty, when he has the power to give help and when the occasion demands his assistance, shows by this very course that he is not forgetful of an injury.

This needs to be observed more diligently, because, commonly, most people weakly conclude that they forgive offenses if they do not retaliate; as if, indeed, we were not taking revenge when we withhold help. You would assist your brother if you thought him worthy; he implores your aid in his necessity; you desert him because he has done you some unkindness. What hinders you from helping him but hatred?

Therefore, only then will we prove that our minds are free from malevolence when we show kindness to those enemies who have ill-treated us. Joseph is said to have spoken to the heart of his brethren, because by addressing them with gentleness and kindness, he removed all their anxieties. As we have seen before, Shechem spoke to the heart of Dinah when he attempted to console her with enticements, in order that, forgetting the dishonor he had done her, she might consent to marry him.