Much is often made of the differences between John’s gospel and the Synoptic Gospels (Matthew, Mark, and Luke) with respect to the deity of Christ. In the gospel of John, Jesus often directly claims to be God incarnate (for example, 8:58). The Synoptics, however, contain few, if any, explicit identifications of Jesus as God. Because of this difference, many liberal scholars have claimed that Jesus never professed to be God incarnate and that John’s gospel cannot be trusted as accurate history.
To conclude from these differences that the Synoptic Gospels know nothing of a divine Christ betrays a failure to read Matthew, Mark, and Luke carefully. Any careful study of the Synoptics demonstrates that their authors were well aware of Jesus’ deity and that He did many things to prove His identity as God incarnate. In other words, while John often prefers to reveal the identity of Christ by recording His direct claims to deity, the Synoptics, and particularly Mark, prefer to reveal Jesus’ deity by recording actions that prove His divinity.
We find one of these actions recorded in today’s passage. The setting is the Sea of Galilee, and the event happened not long after Jesus and His disciples departed the crowd of five thousand men whom Jesus had miraculously fed (Mark 6:45–47). A great storm arose, putting the disciples in great danger (v. 48a). During the fourth watch of the night (3–6 a.m.), Jesus walked on the water out to them, and the winds ceased (vv. 49–51).
Christ’s walking on water was a revelation of His deity. In the Old Testament, only God can control the wind and the sea, and He is even said to walk or trample on the waves in passages such as Job 9:8. By walking on water, Jesus showed that He shares the same abilities as God Himself and is therefore true deity. Furthermore, the English phrase “it is I” spoken by Jesus (v. 50) translates the Greek phrase egō eimi. That is significant because God uses egō eimi to describe Himself in Exodus 3 (in the Greek translation of the Hebrew Bible), and the same phrase is used repeatedly by Jesus in John’s gospel. Mark 6:47–52, therefore, shows us by recording Jesus’ actions and words that Jesus is the incarnate Creator.
At the time, the astounded disciples did not realize what was going on, not because of intellectual dullness but due to hardness of heart (v. 52). Dr. R.C. Sproul writes in his commentary Mark, “When people fail to understand the identity of Christ, it is not because they are unintelligent; it is because their hearts are recalcitrant.”