'Angel of the Lord' in the Bible

The Angel of the Lord found her by a spring of water in the wilderness, the spring on the way to Shur.

Then the Angel of the Lord said to her, “You must go back to your mistress and submit to her mistreatment.”

The Angel of the Lord also said to her, “I will greatly multiply your offspring, and they will be too many to count.”

Then the Angel of the Lord said to her:You have conceived and will have a son.You will name him Ishmael,for the Lord has heard your cry of affliction.

But the Angel of the Lord called to him from heaven and said, “Abraham, Abraham!”He replied, “Here I am.”

Then the Angel of the Lord called to Abraham a second time from heaven