'Messenger' in the Bible

For the lips of a priest should preserve knowledge, and men should seek instruction from his mouth; for he is the messenger of the Lord of hosts.

“Behold, I am going to send My messenger, and he will clear the way before Me. And the Lord, whom you seek, will suddenly come to His temple; and the messenger of the covenant, in whom you delight, behold, He is coming,” says the Lord of hosts.