'Angel of the Lord' in the Bible

And they answered the angel of the LORD, that stood among the myrtle trees, and said, 'We have gone through the world: and behold all the world dwell at ease, and are careless.'

And he showed me Joshua the high priest, standing before the angel of the LORD, and Satan stood at his righthand to resist him.

He said moreover, 'Set a fair mitre upon his head; So they set a fair mitre upon his head, and put on clothes upon him, and the angel of the LORD stood there.

Then the angel of the LORD testified unto Joshua, and spake,

In that day shall the LORD defend the citizens of Jerusalem: so that the weakest then among them shall be as David: and the house of David shall be like as God's house, and as the Angel of the LORD before them.