Acts 4:18 “Then they called them in again and commanded them not to speak or teach at all in the name of Jesus. ¹⁹But Peter and John replied, ‘Judge for yourselves whether it is right in God’s sight to obey you rather than God. ²⁰For we cannot help speaking about what we have seen and heard.’” 

Acts 5:29 “Peter and the other apostles replied: ‘We must obey God rather than mere mortals!’”

Peter and John wanted to cooperate with the authorities. But on occasion they felt they simply could not, in good conscience, comply with what the authorities were asking them to do. They felt morally obliged to obey God, rather than mere mortals.