Malachi was the last of the Old Testament prophets, c. 420 BC. The book of Malachi (one of the minor prophets) is the last book of the Christian Old Testament. The book of Malachi ends with God's promise to send Elijah. Jews and Christians generally agree that Elijah will return before the Messiah. It is a common Jewish practice to set up a fifth cup for Elijah while observing the Passover Seder. Some Christians identify Elijah with John the Baptist, either as Elijah himself or as a typification of Elijah (cf. Matthew 11:14, Matthew 17:11-13; Luke 1:12-17; John 1:21-25), or as Elijah himself at the Transfiguration (Matthew 17:3). Some Christians believe that Elijah will return to herald the Second Coming.