Acts 7:40

‘Saying to Aaron, “Make us gods who will go before us, for as for this Moses, who led us forth out of the land of Egypt, we do not know what is become of him.” '

Rather than responding to the living oracles they chose that Aaron should make them dead replacement gods, for they did not know where Moses had gone. Even at the very mountain of God they had turned to idolatry and the worship of a molten image, and had spurned their deliverer. They had refused the words of Moses and thrust him away.

Let the court consider therefore how these very people of God from whom they were descended had been blasphemers against God, and had spurned the Law of Moses. ‘Not knowing what had become of him' was similar to what Jesus had said people would say once He had been crucified (John 7:34).