'Angel of God' in the Bible

The angel of God said to him, "Take the meat and the unleavened cakes and put [them] on this rock; pour the broth [over it]." And he did so.

And the woman came and told her husband, saying, "A man of God came to me, and his appearance [was] like the appearance of an angel of God, very awesome. I did not ask him from where he [came], and he did not tell me his name.

And God listened to the voice of Manoah, and an angel of God came again to the woman; she [was] sitting in the field, but Manoah her husband was not with her.