Abide in me, and I in you. As the branch cannot bear fruit by itself, unless it abides in the vine, neither can you, unless you abide in me. I am the vine; you are the branches. Whoever abides in me and I in him, he it is that bears much fruit, for apart from me you can do nothing.
(John 15:4-5 ESV)
We don't bear fruit by effort. Fruit comes from abiding, living, remaining in the vine - Jesus. The fruit comes from being part of the vine. As Paul Tripp describes below, so much of our effort in the Christian life is nothing more than nailing apples to a tree that is not growing them.
Jesus is the source of life and fruit (v5), he speaks and we are clean (v3). He is the root and we grow when we are attached to him.