Acts 7:39

To whom our fathers would not obey, but thrust him from them, and in their hearts turned back again into Egypt,

The verse describes Israel at the making of the golden calf, when the leaders called for gods to go before them. Though they had promised to obey all the Lord had said, they grew weary waiting for Moses to return with further instruction, and, stirred by men not truly converted who invented reasons for his delay, they turned back in their hearts to Egypt. In doing so they exchanged the living God for gods made by their own apostasy and threw off the charter by which they were incorporated as a nation.

The fathers refused to obey Moses, God's appointed leader, thrust him from them and rejected him, and in their hearts turned back toward Egypt. The voice they refused to heed was Christ's, for the voice of Christ spoke through the patriarchs and prophets. Their rebellion belonged to a wider history of resisting God and His guidance, including persecuting the prophets. The people confronting Stephen repeated that resistance by resisting the Holy Spirit as their fathers had. They repeated the pattern by rejecting and crucifying Christ, the Just One foretold by the prophets.

The verse belongs to Stephen's account of Israel's history, which presents Christ as the one revealed through the Old Testament and to whom the Scriptures point. That preaching of Christ from the Old Testament scriptures, beginning with Moses and the prophets, gave inspired proof of his mission, suffering, death, resurrection and ascension, and proved his identity with the Messiah through the testimony of Moses and the prophets. The sermon containing the verse was remembered by Saul when Christ was revealed to him; words once condemned as blasphemy then appeared true and showed that Jesus was the promised Messiah. The testimony containing the verse led to Stephen's stoning, at which Saul stood by consenting, after which Saul continued breathing out threatenings and slaughter against the disciples and sought authority to bind believers before he was met near Damascus.