To this day some Jews remember Elijah at circumcisions and Passover meals believing that he will return in our age. The Jews in our passage were anticipating it then. Consider what God promises, through the prophet Malachi, in the last passage of the Old Testament:
“Behold, I will send you Elijah the prophet before the great and awesome day of the LORD comes. And he will turn the hearts of fathers to their children and the hearts of children to their fathers, lest I come and strike the land with a decree of utter destruction.”Jesus understood this promise and said that it was fulfilled in John the Baptist saying that John's purpose in coming was restoration - of family relationships (as Malachi prophesied) and of a relationship with God. John's message of repentance speaks deeply to the heart of that restoration.. as our hearts turn they behold the open arms of our heavenly Father.
The Lord goes on to speak of the way that unrepentant people treated John and how they would soon treat him. In a sense Jesus still embodies the message of Elijah today as he, through the work of the Holy Spirit, restores broken and hurting people to Himself. The message is still restoring the hearts of children to their heavenly Father.
Come Holy Spirit and restore the hearts of my hurting friends to their heavenly Father.