'Messenger' in the Bible

The oracle (burdensome message) of the word of the Lord to Israel through [My messenger] Malachi.

For the priest's lips should keep knowledge, and they should seek the law at his mouth: for he is the messenger of the LORD of hosts.

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.