This is not a joke. Look him in the eyes and say, "He has mercy on whom He desires, and He hardens whom He desires. You will say to me then, "Why does He still find fault? For who resists His will?" On the contrary, who are you, O man, who answers back to God? The thing molded will not say to the molder, "Why did you make me like this," will it? Or does not the potter have a right over the clay, to make from the same lump one vessel for honorable use and another for common use? What if God, although willing to demonstrate His wrath and to make His power known, endured with much patience vessels of wrath prepared for destruction? And He did so to make known the riches of His glory upon vessels of mercy, which He prepared beforehand for glory, even us, whom He also called, not from among Jews only, but also from among Gentiles."

I think that would hit the nail on the head. He is setting himself above God which is foolish and "more righteous" than God. He may be offended initially but he should thank you for an appropriate verse - the medicine for the sickness.

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Bryan Wiley
Southern Baptist Theological Seminary
Reformed Baptist Church
Louisville, Kentucky