'Covenant' in the Bible

And ye shall know that I have sent this commandment unto you, that my covenant might be with Levi, saith the LORD of hosts.

My covenant was with him of life and peace; and I gave them to him for the fear wherewith he feared me, and was afraid before my name.

But ye are departed out of the way; ye have caused many to stumble at the law; ye have corrupted the covenant of Levi, saith the LORD of hosts.

Have we not all one father? hath not one God created us? why do we deal treacherously every man against his brother, by profaning the covenant of our fathers?

Yet ye say, Wherefore? Because the LORD hath been witness between thee and the wife of thy youth, against whom thou hast dealt treacherously: yet is she thy companion, and the wife of thy covenant.

Behold, I will send my messenger, and he shall prepare the way before me: and the Lord, whom ye seek, shall suddenly come to his temple, even the messenger of the covenant, whom ye delight in: behold, he shall come, saith the LORD of hosts.