"Every branch in me that beareth not fruit he taketh away: and every [branch] that beareth fruit, he trimmeth it, that it may bring forth more fruit" (John 15:2). Though the branch may have the sap in it, or a Christian have the Holy Spirit in him, there can be so many things interfering with fruit production that no one could tell from simply looking at it. Jesus' role is to provide life. The Father's role is to remove the things that interfere with that life and its goal: God's glory. And if God gets no cooperation from the Christian on the pruning, then He removes the branch altogether. The sap may still be in it, and one can say "once saved, always saved." But God's attitude towards both unfruitful believers and professing non-believers is that if there is no fruit, then it should not be cluttering His world.
Jesus adds "I am the vine, ye are the branches: He that abideth in me, and I in him, the same bringeth forth much fruit: for without me ye can do nothing" (John 15:5). Jesus' claim that without Him "ye can do nothing" echoes the statements of Jehovah in Isaiah 43:3, 11, and 45:21, which are summarized as "I, even I, am the LORD; and besides me there is no saviour" (Is. 43:11). The question first opened up by Cain was "How is a man to be saved?" It is here answered: without Jesus you can do nothing. Cain was the model for all who would come to God through their own good works rather than by the life (or merit) of another. Jesus says that without that ultimate substitute which all the other sacrifices pointed to, you cannot do anything to please God. He is the only Savior and God, a doctrine echoed in 1 Timothy 1:1, Titus 2:13, and Jude 1:25.
"If a man abideth not in me, he is cast forth as a branch, and is withered; and men gather them, and cast [them] into the fire, and they are bu
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