Albert Barnes Commentary Acts 7:9

"And the patriarchs, moved with jealousy against Joseph, sold him into Egypt: and God was with him," — Acts 7:9 (ASV)

Moved with envy. That is, dissatisfied with the favour which their father Jacob showed Joseph, and envious of the dreams which indicated that he was to be raised to remarkable honour above his parents and brothers (Genesis 37:3–11).

Sold Joseph into Egypt. Sold him, that he might be taken to Egypt. This was done at the suggestion of Judah, who advised it that Joseph might not be put to death by his brothers (Genesis 27:28). It is possible that Stephen, by this fact, might have designed to prepare the way for a severe rebuke of the Jews for having dealt in a similar manner with their Messiah.

But God was with him. God protected him, and overruled all these wicked deeds, so that he was raised to extraordinary honours.