Book of Malachi is also the name of a person, Malachi.

Malachi, a prophet in the days of Nehemiah, directs his message of judgement to a people plagued with corrupt priests, wicked practices, and a false sense of security in their privileged relationship with God. Using the question-and-answer method, Malachi probes deeply into their problems of hypocrisy, infedelity, mixed marriages, divorce, false worship, and arrogance. So sinful has the nation become that God's words to the people no longer have any impact. For four hundred years after Malachi's ringing condemnations, God remains silent. Only with the coming of John the Baptist (prophesied in Malachi 3:1) does God again communicate to His people through a prophet's voice.

The meaning of the name Mal'aki ("My Messenger") is probably a shortened form of Mal'akya, "Messenger of Yahweh," and it is appropriate to the book which speaks of the coming of the "messenger of the covenant" ("messenger" is mentioned three times in Malachi 2:7 and Malachi 3:1). The Septuagint used the title Malachias even though it also translated it "by the hand of his messenger." The Latin title is Maleachi.