N. T. Wright makes it painfully clear that it’s difficult (if not impossible) to understand Jesus fully and rightly without having a deep knowledge of the Old Testament:

Equally impressive are the strong hints, throughout the gospels, that Jesus was modelling his ministry not on one figure alone, but on a range of prophets from the Old Testament. Particularly striking is his evocation of the great lonely figure Micaiah ben Imlach (1 Kings 22), who, when asked about the coming battle, predicted the death of Ahab, king of Israel, by saying, ‘I saw all Israel scattered upon the mountains, as sheep that have no sheperd.’ Jesus, looking at the crowds, takes pity on them, because that is what they remind him of: leaderless sheep. Like Ezekiel, Jesus predicts that the temple will be abandoned by the Shekinah, left unprotected to its fate. Like Jeremiah, Jesus constantly runs the risk of being called a traitor to Israel’s national apsirations, while claiming all the time that he nevertheless is the true spokesman for the covenant god. This, as we shall see, lies behind a good part of the story of Jesus’ action in the Temple, and his subsequence ‘trial’: Jesus has predicted the destruction of the Temple and is on trial not least as a false prophet. Jesus replies to earlier critics and questioners with the sign of the prophet Jonah. Jonah was predicting immenent judgment on Nineveh, following his adventure with the fish; Jesus is predicting imminent judgment on Israel, and a similar sign will validate his message too. He is constantly redefining what the coming day will mean for Israel, warning her, like Amos, that it will be a day of darkness, not of light. Like Amos, too, he implies that the people of god are to be judged as the climax of the divine judgment upon all nations. The judgment which he announces upon Israel is sketched with the help of prophetic passages relating to the judgment of Jerusalem by Babylon, and also, more terrifyingly, passages which speak of the divine judgment upon Babylon itself.

Above all, Jesus adopts the style of, and consciously seems to imitate, Elijah. Here we are again in an interesting position vis-à-vis the sources. It is clear from all three synoptics that they, and presumably with them the early church as a whole, regard John the Baptist as in some sense Elijah redivivus. They nevertheless portray Jesus as acting in Elijah-like ways, and show that the disciples were thinking of Elijah-typology as giving them a blueprint for his, and their own, activity. Jesus himself, explaining the nature of his work, is portrayed using both Elijah and Elisha as models. Again, it is highly unlikely that the early church, seeing Jesus as the Messiah and hence John as Elija, created this identification out of nothing. However, at the same time, though John himself seems to have thought that Jesus was to be the new Elijah, Jesus actually returned the compliment. We begin here to see both parallel and distinction. Jesus’ ministry is so like that of Elijah that they can be easily confused. He too is announcing to the faithless people of YHWH that their covenant god will come to them in wrath. But at the same time he is also acting out a different message, one of celebration and inauguration, which bursts the mould of the Elijah-model.

From all of this it should be clear that Jesus regarded his ministry as in continuity with, and bringing to a climax, the work of the great prophets of the Old Testament, culminating in John the Baptist, whose initiative he had used as his launching-pad.

—N. T. Wright, Jesus and the Victory of God