Jewish mentors expected Elijah the Prophet to appear as a forerunner of the Messiah as told in Malachi 4:5-6, 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.