The Old Testament closes with this amazing prophecy of Malachi: "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" (Malachi 4:5-6).
This prophecy was fulfilled in great measure in the ministry of John the Baptist. An angel appeared to John’s father and prophesied that his son would turn many in Israel to the Lord and that "he shall go before him in the spirit and power of Elias (Elijah), to turn the hearts of the fathers to the children, and the disobedient to the wisdom of the just; to make ready a people prepared for the Lord" (Luke 1:17).
Jesus, speaking to His disciples about John the Baptist, said: "And if ye will receive it, this is Elias, which was for to come" (Matthew 11:14). He added, "He that hath ears to hear, let him hear" (verse 15). I believe Jesus was asking them to see the spiritual significance of John's coming, as prophesied, in the spirit and power of Elijah.
John was anointed with the same fearless Spirit and power which was upon Elijah. He spoke openly about the sins of disobedient, pleasure-seeking people of his day. Christ was soon to appear and this mighty man of truth suddenly came on the scene to prepare a people for the Lord. This wilderness prophet was sent to turn the hearts of the people (which is the truest definition of repentance) to the Lord. John preached repentance, restitution, purity of heart, justice, and a practical walk of holiness to correspond with an open confession of sins.
I believe the prophet Malachi, as well as other Old Testament prophets, speaks of a company of holy people who will be raised up just prior to Christ's second coming. They will minister under the very same Spirit and power that rested upon Elijah and John the Baptist.
This last-day Elijah company of believers will heed the prophecy of Isaiah, "Cry aloud, spare not, lift up thy voice like a trumpet, and shew my people their transgression, and the house of Jacob their sins" (Isaiah 58:1). These are the watchmen upon the walls, "which shall never hold their peace day nor night . . . and give him no rest, till he establish, and till he make Jerusalem a praise in the earth" (Isaiah 62:6-7).