Jesus is teaching his apostles how to carry on His work when He ascends back to the Father. He illustrates the branch (disciples) producing fruit by abiding in the Vine (Jesus).
There are three basic fruits the Lord bears in the lives of His children. They are: (1) Sanctification --- We become more like Jesus; (2) Spirituality --- We behave more like Jesus; (3) Souls --- We are burdened like Jesus.
Not every branch abides in the Vine as it should. It’s still attached, but It‘s fruitless, withered, weak and empty. But the closer believers abide in Christ, the more His life flows through us to produce the fruit He desires. Abiding in Christ gives a settled assurance, a relationship with the Father and His Son, and joy unspeakable and full of glory. And prayers get answered.