As may be seen from Jn 6:17, Jesus Christ, having commanded the disciples to set out alone for the western side of the sea, promised to come to them in the boat at some point on the shore.
From this one may conclude that the disciples first had to keep a coastal course toward the northern end of the sea.
But suddenly a northeast wind arose and began driving the boat southwestward into the depths of the sea. In this condition they probably wished to reach as soon as possible the place to which they had been commanded to sail by the Lord.
Nevertheless, they struggled until the fourth watch, but did not reach the shore. At that time, when they were in the midst of the sea (Matthew and Mark), having sailed about twenty-five or thirty stadia (John), they saw Jesus walking on the waters.
Mark adds that He was making His way past them (Mk 6:48). Exhausted by the struggle with the waves and by fear for their lives, they did not believe their eyes.
They took Him for a phantom, and fear seized them still more. But Jesus Christ encouraged them with His voice.
Here follows the account belonging to the Evangelist Matthew alone, concerning the Apostle Peter walking on the waters (Mt 14:28-31).
The Evangelists end the story differently. First of all, John seems to contradict Matthew and Mark.
According to the latter, the disciples received Jesus, and in Matthew also Peter, into the boat, and the wind ceased. John says, “They wanted to receive Him into the boat, and immediately the boat reached the shore where they were going” (Jn 6:21).
It might seem that the meaning is this: the disciples only wanted to receive Jesus into the boat, but this proved unnecessary, because the boat reached the shore.
Yet it is not necessary to represent the matter in this way. “They wanted” is contrasted with their previous state, their fear that they were seeing not Jesus, but a phantom.
That fear had now passed, and they wanted to receive Him into the boat, whereas before they wanted to flee from Him.
“Immediately” is contrasted with their previous very prolonged and unsuccessful struggle with the waves. It is not necessary to understand the word as meaning that Christ did not have to sail several stadia with the disciples.
Five or ten stadia still remained to the shore. “Immediately” means only that the sailors, now with Jesus, reached the shore as quickly as before they had long and unsuccessfully striven to reach it.
What the first Evangelists indicated by the words “and the wind ceased,” John expresses with the words, continuing the same thought: “immediately the boat reached the shore.”
Then Matthew and Mark seem to contradict one another. The first says that the disciples worshiped the Lord and confessed Him to be the Son of God after they were convinced of the miracle of Jesus Christ walking on the waters.
The latter says (Mk 6:51-52) that the disciples’ heart was hardened, and that they had not understood the miracle of the loaves, but only wondered and were amazed at the new miracle.
From this, however, it follows only that the disciples, struck by the greatness of the miracle, bowed before the Lord and confessed Him as the Messiah.
At the same time, they wondered that Christ performed such extraordinary and unheard-of deeds. The Apostle Peter, from whose words Mark speaks here, observes such a disposition and reflection in the depth of the disciples’ souls.
He considers it a defect, a hardening of heart. According to him, the miracle of the feeding was so great that after it there should have been no room for any questions.
They should not have questioned the power or possibility for Jesus Christ to perform even such a miracle as walking on the waters.
Since the first three Evangelists say that evening had already come before the feeding (Mt 14:15), a second evening must be understood here. Among the Jews, the first was from three to six o’clock, and the second from sunset until nightfall.
In the time of Christ the Jews divided the night into four watches of three hours each. The fourth watch was from three to six o’clock in the morning.
The whole sea from east to west measured forty stadia. According to John, therefore, the disciples were in the middle of the sea.
But by the expression “in the midst of the sea,” the Evangelists Matthew and Mark only mean that the disciples were far from shore. Consequently, amid the disturbance of the sea, they were in danger.