“But when the time of the promise drew near which God had sworn to Abraham, the people grew and multiplied in Egypt 18 till another king arose who did not know Joseph. 19 This man dealt treacherously with our people, and oppressed our forefathers, making them expose their babies, so that they might not live. 20 At this time Moses was born, and was well pleasing to God; and he was brought up in his father’s house for three months. 21 But when he was set out, Pharaoh’s daughter took him away and brought him up as her own son. 22 And Moses was learned in all the wisdom of the Egyptians, and was mighty in words and deeds.
23 “Now when he was forty years old, it came into his heart to visit his brethren, the children of Israel. 24 And seeing one of them suffer wrong, he defended and avenged him who was oppressed, and struck down the Egyptian. 25 For he supposed that his brethren would have understood that God would deliver them by his hand, but they did not understand. 26 And the next day he appeared to two of them as they were fighting, and tried to reconcile them, saying, ‘Men, you are brethren; why do you wrong one another?’ 27 But he who did his neighbor wrong pushed him away, saying, ‘Who made you a ruler and a judge over us? 28 Do you want to kill me as you did the Egyptian yesterday?’ 29 Then, at this saying, Moses fled and became a dweller in the land of Midian, where he had two sons.
30 “And when forty years had passed, an Angel of the Lord appeared to him in a flame of fire in a bush, in the wilderness of Mount Sinai. 31 When Moses saw it, he marveled at the sight; and as he drew near to observe, the voice of the Lord came to him, 32 saying, ‘I am the God of your fathers—the God of Abraham, the God of Isaac, and the God of Jacob.’ And Moses trembled and dared not look. 33 ‘Then the Lord said to him, “Take your sandals off your feet, for the place where you stand is holy ground. 34 I have surely seen the oppression of My people who are in Egypt; I have heard their groaning and have come down to deliver them. And now come, I will send you to Egypt.”’
35 “This Moses whom they rejected, saying, ‘Who made you a ruler and a judge?’ is the one God sent to be a ruler and a deliverer by the hand of the Angel who appeared to him in the bush. 36 He brought them out, after he had shown wonders and signs in the land of Egypt, and in the Red Sea, and in the wilderness forty years. — Acts 7:17-36.
Stephen relates how God chose Moses to be the ruler and deliverer of His people, right from his birth up to the forty wilderness years.