True disciples of Jesus bear spiritual fruit, as Jesus emphasizes in John 15:1–6. This fruit, of course, is not what saves us. Salvation precedes fruit—a branch must be attached to the vine to be fruitful, for a branch does not produce fruit on its own (vv. 3–4). Yet, as Dr. R.C. Sproul writes in his commentary John, “While we are justified by faith apart from works, we are justified by faith unto works.” Our works—which are part of the fruit we produce—cannot declare us righteous before God, but if we have no good works, we have no saving faith (James 2:14–26).
We speak of good works as part of the fruit that true Christians bear because John’s gospel and the rest of the New Testament make that connection. For instance, John the Baptist announced the inbreaking of God’s kingdom by calling people to “bear fruits in keeping with repentance” (Luke 3:8). What could such fruit be but a life that is oriented to obeying God? Jesus says that if we love Him, we will keep His commandments (John 15:15). We will do the deeds that He commands us to do. More specifically, the fruit we are called to bear is love for others, particularly love for Jesus’ other disciples, for we are to love one another in the Christian community as Christ has loved us (v. 12). Such love is costly, as it causes us to be willing to go so far as to lay down our lives for others as we imitate Jesus’ example (v. 13).
In our fallenness, we cannot do any of that on our own. It requires a vital union with Christ whereby He communicates to us the desire and power to love Him and to love others (v. 5). John 15:7 emphasizes that union yet again, as it records Jesus’ words that when we abide in Christ and He abides in us, our prayers will be effective. In other words, when we lean only on Christ and seek to have His teaching shape our lives, God will grant us fruitfulness when we pray for it. This is not a guarantee that obeying Christ means we will receive everything we could ever want; rather, as Christ’s words abide in us, we will come more and more to pray for what He wants, and therefore we will see results.
John Calvin comments on today’s passage that Jesus “means that his people will or desire not riches, or honors, or any thing of that nature, which the flesh foolishly desires, but the vital sap of the Holy Spirit, which enables them to bear fruit.” The true branches of Christ abide in Him by faith and seek to do His will, and He nourishes them by the Spirit to pray that His will be done.