Matthew Poole and continuators on Acts 7:30

30 And when fourty 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.

So long it pleased God to try Moses his faith, and his peoples patience:

to the Desert of Arabia, where the Law was afterwards delivered, Exod. 18.5. and 19: 3.

Not a Created, but the Increated Angel, the Angel of the New-Covenant, as may be seen ver. 32. and by Moses putting off his shoes because the place was holy, Exod. 3.2, 5. he is also in the four first verses of that Chapter, 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 shew 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.