If you have been a Christian for a number of years, you have likely known at least one person who has walked away from the faith. The person may have seemed to be an enthusiastic follower of Jesus, but he did not endure in following the Lord. As far as you can tell, he is an apostate, one who has abandoned his profession of the Christian faith.
The New Testament tells us that there will be some people who seem to be disciples of Jesus who later prove not to be His followers. We have already seen such followers in John’s gospel. At a Passover feast, some people “believed” in Jesus but He did not entrust Himself to them; He did not receive their faith (John 2:23–24). After the Bread of Life discourse, many of Jesus’ disciples “turned back and no longer walked with him” (6:66). There is, then, a kind of “discipleship” that is merely temporary and does not persevere to the end.
By the time we get to John 8:59, we will see that this in-appearance-only discipleship apparently characterized most, if not all, of the Jews who believed after hearing Jesus give the teaching recorded in verses 12–29. These are the Jews to whom Jesus turns in today’s passage in order to describe the nature of true discipleship. The idea is that Jesus has seen the Jews believe in Him and now He is going to probe further to see if their belief is saving or just temporary.
Jesus says, “If you abide in my word, you are truly my disciples” (v. 31). Note that He does not say they “will be” His disciples if they abide in His word, in His teaching. We do not earn the status of disciples by following Jesus, though following Him is necessary. Instead, when we turn to Christ in saving faith, we receive and rest in Him as Savior. And the result is that we abide in His word. True disciples of Jesus follow Him not just at the beginning, but also to the end. John Calvin comments, “He distinguishes his followers from hypocrites by this mark, that they who falsely boasted of faith give way as soon as they have entered into the course, or at least in the middle of it; but believers persevere constantly to the end.”
True disciples are marked not by sinless perfectionism but by abiding in the words, the teaching, of Christ. They do not just confess Jesus with their mouths, but they trust in Him with their hearts and prove it by seeking to do His will, repenting where they fall short, and returning again and again to Him to learn His way.