'Covenant' in the Bible

"You will know that I sent this commandment to you in order to continue my covenant with Levi," says the LORD of the Heavenly Armies.

"My covenant with him was for life and peace, and I gave the commandments to him so he would fear me. He did fear me as he stood in my presence.

"But you priests turned aside from the way, and by your teaching you caused many to stumble. You have violated the covenant of Levi," says the LORD of the Heavenly Armies.

Do we not have one father? Has not one God created us? Why does each of us act deceitfully, each man against his own brother, to profane the covenant of our ancestors?

Yet you ask, "For what reason?' Because the LORD acts as a witness between you and the wife of your youth, because you were unfaithful to her, your partner, the wife of your covenant.

"Watch out! I'm sending my messenger, and he will prepare the way before me. Then suddenly, the LORD you are looking for will come to his Temple. He is the messenger of the covenant whom you desire. Watch out! He is coming!" says the LORD of the Heavenly Armies.