Forty years; so long it pleased God to try Moses's faith, and his people's patience. Mount Sinai, in the desert of Arabia, where the law was afterwards delivered, Exodus 18:5, Exodus 19:3. An angel; not a created, but the uncreated Angel; the Angel of the new covenant, as may be seen Acts 7:32, and by Moses putting off his shoes because the place was holy, Exodus 3:2,5; he is also in Exodus 3:4 called the Lord. God still appeared in such a manner as was most instructive to them he appeared to, and to us; as here in a flame of fire in a bush to show that he was with his people in all their sufferings, and would so provide, that they should not be consumed by them; they might be purified, but should not be destroyed.
Related Commentaries of Acts 7:30
Acts 7:30
30 And when forty years were expired, there appeared to him in the wilderness of mount Sina an angel of the Lord in a flame of fire in a bush.