'Have Mercy' in the Bible

Then the angel of the LORD answered and said, O LORD of hosts, how long wilt thou not have mercy on Jerusalem and on the cities of Judah, against which thou hast had indignation these threescore and ten years?

This is what the Lord of armies has said: Let your judging be upright and done in good faith, let every man have mercy and pity for his brother:

And I will strengthen the house of Judah, and I will save the house of Joseph, and I will bring them again to place them; for I have mercy upon them: and they shall be as though I had not cast them off: for I am the LORD their God, and will hear them.