Romans 9:17-19

For just as God said to Pharaoh: “I raised you up as ruler of Egypt for this reason, that I might make you an example of how I demonstrate my miracle power. For by the example of how I deal with you, my powerful name will be a message proclaimed throughout the earth!” So again we see that it is entirely up to God to show mercy or to harden the hearts of whomever he chooses. Well then, one might ask, “If God is in complete control, how could he blame us? For who can resist whatever he wants done?”