'Angel of God' in the Bible

Then thine handmaid said, 'I pray God that the word of my lord the king may be immutable. For my lord the king is as an angel of God, in hearing of good or bad.' And therefore the LORD thy God be with thee."

And the turning of my tale another way, that made thy servant Joab. And so I see that my lord is wise, even as an angel of God, to understand all things that are in the earth."

And he hath thereto complained on thy servant unto my lord the king. But my lord the king is as an Angel of God: do therefore what seemeth best in thine eyes.