Based on Malachi 4:5, Jesus confirms the teaching that Elijah comes first as orthodox. Elijah brings restoration of relationships (Malachi 4:6) in repentance and forgiveness (Luke 1:16; Matthew 3:6). To restore all things
(Matthew 17:11) is to reposition everything: restoring right order to the whole world, specifically as this order is shown in Israel—thus preparing for the coming of the Messiah. In Malachi 4:5, alluded to in Matthew 11:14, there are more details about the work of the forerunner that are not mentioned in Matthew 17:1–27: see Luke 1:17 and Isaiah 40:3. In Acts 3:21, what is said here about the forerunner is also said of the Messiah, and much more broadly.
Jesus not only affirms the prophecy of Elijah as the Messiah’s herald, but also stresses how the prophecy was fulfilled in John the Baptist (see also Matthew 11:10–14), who came in the spirit and power of Elijah (Luke 1:17), just as the Messiah comes in the line of David’s promised kingship (Jeremiah 30:9; Ezekiel 34:23, Ezekiel 37:24; Hosea 3:5). John was the Elijah
who would serve as the Messiah’s herald (Malachi 3:1, Malachi 4:5).
Jesus confirms, on the basis of Malachi 4:5, that the doctrine of the scribes concerning Elijah coming first is orthodox. The restoration that Elijah brings is spiritual and moral, not political. Its essence is the restoration of mutual relationships (Malachi 4:6) through repentance and forgiveness (Luke 1:16; Matthew 3:6).1
To restore all things
(Matthew 17:11) means to reposition everything anew, that is, to restore the proper order to the whole world, specifically as this order is manifested in Israel—and this to prepare for the coming of the Messiah. In the prophecy of Malachi 4:5 alluded to in Matthew 11:14, there is a further specification regarding the work of the forerunner, which remains unmentioned here: see Luke 1:17 and also Isaiah 40:3. In our context we must, because it concerns the expectation of the Jews, restrict the meaning here to Israel. In Acts 3:21, what is said here about the forerunner is also said of the Messiah himself, and that in the broadest sense of the word.2
Jesus goes further than merely affirming the prophecy of Elijah as a forerunner to the Messiah by highlighting that the prophecy has actually already been fulfilled in John the Baptist (see also Matthew 11:10–14). Jesus teaches that this prophecy is fulfilled in John the Baptist, who came in the spirit and power of Elijah (Luke 1:17), just as the Messiah comes in the line of David’s promised kingship (Jeremiah 30:9; Ezekiel 34:23, Ezekiel 37:24; Hosea 3:5). The Baptist was indeed the Elijah
who, according to the prophecy, would serve as the forerunner to the Messiah (Malachi 3:1, Malachi 4:5).3
11 He answered, “Elijah does come, and he will restore all things.