OUR LIFE IS IN HIM
John 15:4 "Abide in me, and I in you. As the branch cannot bear fruit of itself, except it abide in the vine; no more can ye, except ye abide in me."
This is a profound truth, that is the key to bearing fruit, but it is so easy to forget. Because the fruit is borne on the branch, it is easy to credit the branch with the fruit, when it is the vine that drew the life from the earth and channeled it through the branch.
Likewise, since we are the branch through which the life of God flows, we sometimes think that it is our own holiness that produces the fruit. The moment we think that way, we are no longer abiding (trusting in; clinging to) in the vine and we will become fruitless if we persist in this mind set.
This is actually a great relief if the believer understands this and applies it properly. It puts all the responsibility on Jesus. Our only responsibility is to respond to His ability. In the same way that you have never seen a branch travailing to bring forth fruit, so all we have to do is labor to enter into His rest (trust and depend) and completely trust Jesus as our source (Heb. 4:11). If we abide in Him, fruit will come naturally.
It's our faith in what Jesus did for us that saved us, and our faith has to continue to be in Christ, not in ourselves, to maintain salvation. Our holiness, righteousness, and justification are gifts that we receive in our spirits through Jesus.
Just like the life of a root is found in the soil, or a branch in the vine, or a fish in the sea, so the believer's true life is found in the union with Christ.