“What would you say to someone who thinks he is too sinful to be saved?”
I’d quote him the words of the apostle Paul: “The saying is trustworthy and deserving of full acceptance, that Christ Jesus came into the world to save sinners, of whom I am the foremost.”
After all, prior to being saved, Paul beat and imprisoned believers and tried to make them blaspheme. As a member of Jewish leadership, he cast his vote against Christians when they were put to death by the Jews.
Can your friend top that?