'Angel of God' in the Bible

Then the woman went to tell her husband. She said, "A man of God appeared to me. He looked like what an angel of God would look like very frightening. I didn't ask him where he had come from and he didn't tell me his name.

God listened to Manoah's request, and the angel of God came again to the woman as she was sitting out in the pasture. But her husband Manoah wasn't with her,