So, to be clear: John the Baptist is a different guy to the John who wrote this particular book. That John is the son of Zebedee, the ‘beloved disciple’, who also most likely wrote 1, 2 and 3 John (shorter letters which appear near the end of the New Testament) and received the vision that spans the book of Revelation. So, kind of a big deal.
But John the Baptist is also kind of a big deal. All four gospels mention him, which is a bit of a clue – and he gets to baptise Jesus – so what is so special about this guy?
A bit of background. Elijah was an old testament prophet, who was active during the time of the divided kingdom in Israel, around 9th century BC. He’s one of the few people in the Bible not to die – when his time comes, he gets taken up to Heaven in a whirlwind (2 Kings 2:11). Malachi – an Old Testament prophet somewhere around 5th century BC – prophesied that God would
“send the prophet Elijah to you before that great and dreadful day of the Lord comes. He will turn the hearts of the parents to their children, and the hearts of the children to their parents; or else I will come and strike the land with total destruction.“ (Malachi 4:5-6)
There’s then a long wait. Christian Bibles place Malachi at the end of the Old Testament, so we go straight from this prophecy (which concludes the Old Testament) into the New Testament, the time where Jesus’ life, death and resurrection would bring about the fulfilment of these prophetic promises. Elijah does appear at the transfiguration (see i.e. Matthew 17) – but Jesus makes it clear in that the prophecy in Malachi was actually talking about John the Baptist – one who is not a literal reappearance of Elijah, but who carries a similar prophetic ministry to him.
“why do the scribes say that first Elijah must come?” He answered, “Elijah does come, and he will restore all things. But I tell you that Elijah has already come, and they did not recognize him, but did to him whatever they pleased. So also the Son of Man will certainly suffer at their hands.” Then the disciples understood that he was speaking to them of John the Baptist.” (Matthew 17:10-13)
Earlier on in Matthew, Jesus had already been speaking incredibly highly of this same man:
A prophet? Yes, I tell you, and more than a prophet. This is he of whom it is written, ‘Behold, I send my messenger before your face, who will prepare your way before you.’ Truly, I say to you, among those born of women there has arisen no one greater than John the Baptist. Yet the one who is least in the kingdom of heaven is greater than he. From the days of John the Baptist until now the kingdom of heaven has suffered violence, and the violent take it by force. For all the Prophets and the Law prophesied until John, and if you are willing to accept it, he is Elijah who is to come. He who has ears to hear, let him hear.” (Matthew 11:9-15)
So we have Malachi (like many of the prophets) prophesying that there is a day of judgement coming – but that before that day comes, God would send another prophet to spare them, by restoring the broken relationship between the great Father and his people. The Jewish people wait for hundreds of years for the re-appearance of Elijah, and as the New Testament begins, Jesus wants them to understand that this prophet has finally come. And what does this long awaited prophet do? How is it exactly that God uses him to restore the hearts of parents to their children, and the hearts of children to their parents, and save them from total destruction? He points people to Jesus.