The false witnesses against Stephen said the same thing they said against Jesus, that the temple would be destroyed. Hmm.
His sermon began with Abram, recounted God's promise, the covenant of circumcision, and the move to Caanan. The rest of the speech is about Egypt. Joseph was delivered to Egypt, "But God was with him." That makes everything alright.
Then Moses grew in word and deed. He WAS a good speaker, contrary to his claim. He'd been trained in Egyptian rhetoric.
When God appeared to Moses in the burning bush and asked him to deliver Israel, Moses repeated the words, the 40-year-old words, of the Israelite that had caused him to flee. He had been playing this over and over in his mind for 40 long years, "Who made you a ruler or judge?"
Then Stephen said, "God made him a ruler and redeemer." Fascinating!