'Lord's' in the Bible

The Lord's angel found Hagar near a spring of water in the desert -- the spring that is along the road to Shur.

Then the Lord's angel said to her, "Return to your mistress and submit to her authority.

I will greatly multiply your descendants," the Lord's angel added, "so that they will be too numerous to count."

Then the Lord's angel said to her, "You are now pregnant and are about to give birth to a son. You are to name him Ishmael, for the Lord has heard your painful groans.

But the Lord's angel called to him from heaven, "Abraham! Abraham!" "Here I am!" he answered.

The Lord's angel called to Abraham a second time from heaven

Then Laban and Bethuel replied, "This is the Lord's doing. Our wishes are of no concern.

But Er, Judah's firstborn, was evil in the Lord's sight, so the Lord killed him.

What he did was evil in the Lord's sight, so the Lord killed him too.

If one of us has it, he will die, and the rest of us will become my lord's slaves!"

Judah replied, "What can we say to my lord? What can we speak? How can we clear ourselves? God has exposed the sin of your servants! We are now my lord's slaves, we and the one in whose possession the cup was found."

"So now, please let your servant remain as my lord's slave instead of the boy. As for the boy, let him go back with his brothers.