Who does God say He will send before the great and dreadful day of the Lord?

Les explains that Revelation 11 describes the appearance of the two witnesses at the beginning of the tribulation. He notes Scripture does not name them, so we cannot be dogmatic, but he speculates one witness is Elijah, since Elijah was taken up without having died. Les then points to Malachi 4:5, where God promises to send Elijah the prophet before the great and dreadful day of the Lord. Malachi 4:6 adds that Elijah will turn the hearts of the fathers to the children and the children to their fathers, lest God come and smite the earth with a curse. Les connects this to Matthew 11, where Jesus speaks of John the Baptist and says, 'if you will receive it,' addressing the Jews.