Exod 32:10

“When he wished that [the fig tree] be uprooted, the event was similar to that earlier one, when the Father said to Moses, "Permit me to destroy the people." He [thus] gave him a reason to intercede with him. Here too he showed the vinedresser that he wished to uproot it. The vinedresser made known his plea, and the merciful one showed his pity, that if, in a further year, [the fig tree] did not yield fruit, it would be uprooted.”

“On another occasion God said to Moses, "Let me alone … that I may consume this people," showing by the words "let me alone" that he can be withheld from doing what he threatens. The prayers of his servant hindered his power. Who, think you, is there now under heaven able to stay God's wrath, to face the flame of his judgment and to say with the apostle, "I could wish that I myself were accursed for my brethren"?”

“Moses resisted God and prevented him from destroying his people when God said to him: "Let me alone, that I may strike this people." Just see the power of Moses! What does God say to him? Let me alone; you are compelling me, your prayers, as it were, restrain me; your prayers hold back my hand. I shoot an arrow; I hurl a javelin; and your prayers are the shield of the people. Let me alone that I might strike down this people. Along with this, consider the compassionate kindness of God. When he says, "Let me alone," he shows that if Moses will continue to importune him, he will not strike. If you, too, will not let me alone, I shall not strike; let me alone, and I shall strike. In other words, what does he say? Do not cease your persistent entreaty, and I shall not strike.”

“And in case you should suppose that he acted like this more from necessity than from charity, God actually offered him another people: "And I will make you," he said, "into a great nation," so leaving himself free to eliminate those others. But Moses wouldn't accept this: he sticks to the sinners; he prays for the sinners. And how does he pray? This is a wonderful proof of his love, brothers and sisters. How does he pray? Notice something I've often spoken of, how his love is almost that of a mother. When God threatened that sacrilegious people, Moses' maternal instincts were roused, and on their behalf he stood up to the anger of God. "Lord," he said, "if you will forgive them this sin, forgive; but if not, blot me out from the book you have written." What sure maternal and paternal instincts, how sure his reliance, as he said this, on the justice and mercy of God! He knew that because he is just he wouldn't destroy a just man, and because he is merciful he would pardon sinners.”