At the beginning of chapter 15, Jesus introduces a new parable to help explain to his disciples what he’s been telling them.
“I am the true vine, and my Father is the gardener. He cuts off every branch in me that bears no fruit, while every branch that does bear fruit he prunes so that it will be even more fruitful…”
And so Jesus compares his followers to branches that are all attached to him. And his says that everyone who attaches themselves to him will at some point feel the sharpness of the blade. Just like a vine, the branches that are worthless and don’t produce any fruit are cut off and thrown away, but the branches that do produce fruit are also cut. But they are not cut off, no, they are pruned so that they can produce even more fruit.
Jesus is saying that his disciples are just like the branches. They are all associated with the main vine, with Jesus. But if the disciples do not reflect the purpose of the main vine, if they have nothing in common with Jesus, if they don’t produce fruit, they will one day be cut off from Jesus, and they will no longer have the choice of bearing fruit or not. What they choose to be in the present is what they will continue to be in the future. If they live now as though they are not attached to Jesus, then in the end they will not be attached to Jesus.
It works the same way for the disciples that truly are changed by Jesus... only with the opposite effect. They are all associated with the main vine, with Jesus. And if they reflect the purposes of the main vine, if they have common-ground with Jesus, if they produce fruit, then when the blade comes they will not be removed from Jesus, but instead they will be brought into even greater alignment with his purposes, and anything in them that is not Christlike will be cut off, they will be pruned, and they will be more and more like their Savior, producing more and more good fruit. What they choose to be in the present is what they will continue to be in the future. If they live now as though they are attached to Jesus, then in the end they will always be attached to Jesus.
“I am the vine; you are the branches. If you remain in me and I in you, you will bear much fruit; apart from me you can do nothing. If you do not remain in me, you are like a branch that is thrown away and withers; such branches are picked up, thrown into the fire and burned…”
So what is this fruit that Jesus is talking about?
A lot of people think that Jesus is saying if you don’t get your friends to become Christians then you’ll end up going to hell. But that’s not what he’s saying at all. Yes, we should want are friends to know Jesus as we know him, but we shouldn’t mistake the fruit for the branches. New branches are new Christians. The fruit is something else. But what?
Well, Jesus, as usual, is alluding to several different Old Testament passages when he talks about vines and branches and fruits.
Jeremiah talks about God stripping away all the branches that do not produce good fruit, and he says the reason this happens is because of idolatry. The people choose to follow after other gods, they forsake the covenant with their God and in the end they wind up being cut off from their God, the source of all life… and they die. Jeremiah compares these people to stallions neighing after any mare that trots by.
And Ezekiel paints the same picture of the useless branches of the vine being burned. He says that vines are not like the trees of the forest. You can’t use the branches of the vine to build a house with. The only thing they’re good for is for making fruit, and if they don’t make fruit, then the only thing they’re good for is kindling for the fire.
Zechariah and Isaiah both speak of the coming Messiah as the true vine whose branches will produce good fruit, the best fruit. They say that in past, God has had to burn branches that were useless. His own people were destroyed because they chose to no longer be his people. Israel was the poisoned vine with unproductive branches, perverting justice and abusing the poor. They rejected the source of all life and died. But in the future, a shoot will pop up and grow from the stump of the vine that was cut down, and the branches of this new vine, this New Israel, the Messiah, Jesus, will produce abundant crops.
Isaiah tells us what the fruit of the branches of the true vine are. The fruit of the Messiah, of Jesus and his followers, is this:
A shoot will come up from the stump of Jesse;
of the Lord will rest on him—
of the Lord.
of the Lord will rest on him—
of the Lord.
-- Isaiah 11:1-9