As we read the Gospel of John, we notice that there is a very distinct transition that takes place at the start of chapter 13. Up until that point, John records the public ministry of the Lord Jesus to the crowds as He offers to them eternal life through faith in His name. But in chapter 13-17, Jesus is alone with His disciples. Now it is not so much the offer of eternal life that John is presenting as the nature of eternal life. Eternal life is not simply life that lasts forever (although that is true), but life that is enjoyed in a living, loving relationship with the Triune God (Father, Son, and Holy Spirit) and is entered now through personal faith in Christ.
When John speaks of believing in His name (John 1:11-12), he is emphasising that we must believe everything the Gospels says about the Lord Jesus— particularly who He is and what He has done for us. And so the Apostle John records seven wonderful “I am” statements spoken by the Lord Jesus that present His unique identity. The last two of these are recorded during the private ministry of Jesus to His disciples, to those who have already believed in His name. It is to them that He says, “I am the vine, you are the branches” (John 15:5).
I am no gardener, but I think even modern city dwellers can understand the imagery that Jesus is using. The vine is the main trunk of the plant that draws up nutrients from the ground and then passes its life out to the branches of the vine to bring forth grapes. The branches of a grape vine have only one purpose and that it to bring forth fruit. You cannot use the branches to make furniture and it doesn’t even make good firewood. So, He plainly states that without Him we can do nothing. And if you cut the branches off, they wither and die. They need to be firmly connected to the life-giving vine to fulfil their God-ordained purpose.
Some people try to do things for God but are not connected to the True Vine, the Lord Jesus. They hope that because of their active participation in humanitarian activities or religious rituals that God is pleased with them; but Jesus says, “Without Me, you can do nothing.” We first need that living, loving relationship that comes through believing in His name to vitally connect us to the True Vine. Then through His powerful life flowing through us, we can produce fruit that is lasting and brings delight to the heart of God.
But there is another key factor that Jesus emphasises here. Not only do we connect to Him through believing in His name, but we need to “abide in Him”. Some translations use the word “remain” instead of abide but that seems to imply effort or works on our part. However, it is resting in Christ and what He has done that we need. We must be dwelling with Him and enjoying fellowship with Him. One author describes it this way:
Believing leads to union with Him, while abiding is communion. Being in Him is the source of life. Abiding in Him is the source of fruit (cf. 1 John 2:6).
S. Lewis Johnson
That is why Christians will often say that Christianity is not about religion; it is about a relationship with God through the Lord Jesus. It is not about my performance, but my participation in His life through faith. It is not about how much I do for Him but about how much I realise all that He has done for me. And the deeper my appreciation of Him, the more effective my service for Him will be, and the more fruit I will bear for His glory.