(Heb. mal’ak, Gr. angelos), an angel, a messenger who runs on foot, the bearer of despatches (Job 1:14; 1 Sam. 11:7; 2 Chr. 36:22); swift of foot (2 Kings 9:18).
Messenger
The word covers more than angels. In Malachi the LORD says, “Behold, I will send my messenger, and he shall prepare the way before me,” and Matthew and Mark both take that line as pointing to the one who came before Jesus. Elsewhere a priest is called a messenger of the LORD, and Haggai the prophet carries a message to the people. Paul uses the word once in a darker way, speaking of a thorn in the flesh as a messenger of Satan. Malachi 3 is the clearest place to begin; then read how the Gospels use it.
8 verses
Haggai
Then spake Haggai the LORD'S messenger in the LORD'S message unto the people, saying, I am with you, saith the LORD.
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.
Behold, I will send you Elijah the prophet before the coming of the great and dreadful day of the LORD:
And he shall turn the heart of the fathers to the children, and the heart of the children to their fathers, lest I come and smite the earth with a curse.
Matthew
For this is he, of whom it is written, Behold, I send my messenger before thy face, which shall prepare thy way before thee.
Mark
As it is written in the prophets, Behold, I send my messenger before thy face, which shall prepare thy way before thee.
2 Corinthians
And lest I should be exalted above measure through the abundance of the revelations, there was given to me a thorn in the flesh, the messenger of Satan to buffet me, lest I should be exalted above measure.
From Easton's Bible Dictionary
Matthew George Easton, 1897