What does Acts 7:19 mean?

In the time of the early church, Jews claimed absolute loyalty to Moses, his Law, and the temple. They still remembered how hundreds of years before, their ancestors' neglect of the law led to exile to Babylon and the destruction of the temple. Even under Roman rule, the Jews tried hard to follow the Law Moses gave them as well as extra manmade traditions meant to give more weight to the Law. Despite this deep devotion, most of the Jews completely missed that God's promised Messiah has come: Jesus. In fact, they claimed that Jesus' followers disrespect Moses, the Law, and the temple. Stephen is showing how just as the traditional Jews are short-sighted in their understanding of Jesus, they also misunderstand God's work in their own history and the meanings of these three pillars of Jewish faith.

God didn't need the land, the Law, or the temple to develop the clan of Abraham into a nation. He used four hundred years of slavery in Egypt to build up the population of His people. Even when Pharaoh demanded all the baby Israelite boys be either killed by their midwives or "exposed"—thrown into the Nile River (Exodus 1:15–22)—God rescued His chosen leader, Moses (Exodus 2:1–10).

In the hundreds of years since that time, God often used foreign nations to discipline the rebellious Israelites. In Stephen's time, the scattered Jews—even his accusers from Africa and modern-day Asian Minor—cling to Moses, the Law, and the temple to define them during their subjugation to the Roman Empire. They miss the truth that they have placed their faith in the tools God gave them to encourage their faith in Him.