Christian, You Are a Branch of the True Vine
You draw your life, your sustenance, from Jesus. As long as you remain in Him, His substance flows in you. Apart from Him, you have no life.
This is a metaphor that illustrates an imperative: remain in Him! Even as a branch must remain attached to the vine in order to bear fruit, you too are called to remain in the True Vine. Only then can you ever fulfill your true function, which is to bear fruit. Apart from the vine, you will never reach fruition, fulfillment, completeness. You will be like a branch cut off and cast aside. To remain, then, is to be fruitful.
Why does it matter? Simply: only by this means will we be able to love one another. Love is the Christly command, and yet in order to obey, we must remain in the one who is love. And this same love is the means by which, ultimately, God receives the glory he deserves. So remain. Stay attached. Draw life. Then you'll grow, put out buds, flower, bear fruit. This is the natural order of the Christian’s life. And your joy will be complete.
Christian, do you believe it? Are you remaining in Him? Are you continuing, day by day, to draw your sustenance, your nurture, from Him alone? Can you say that your love for God and for others is like His was? Oh, not its same purity and perfection, of course, but bearing the resemblance, as of the same genus. Fruit of the same vine.
And then he says, if you do this, if you remain in me, my Father will give you what you ask in my name. You see, to draw upon Jesus is to draw upon the Father. Then, when your love for others, which is only the love you draw from the Vine, manifests itself in fervent intercession for those you love, the Father will give you what you ask. Result: your joy, His glory.