If the story of Jesus calming the sea (Mk. 4:35-41) has become so familiar that it no longer conveys the very real terror felt by the apostles, perhaps the drawing above by Jan Luykens helps.
Ps. 107:23-32 could also help. It reads like a prophecy of the event itself:
“Some went down to the sea in ships, doing business on the great waters; they saw the deeds of the Lord, his wondrous works in the deep. For he commanded, and raised the stormy wind, which lifted up the waves of the sea. They mounted up to heaven, they went down to the depths; their courage melted away in their evil plight; they reeled and staggered like drunken men, and were at their wits’ end.
“Then they cried to the Lord in their trouble, and he delivered them from their distress; he made the storm be still, and the waves of the sea were hushed. Then they were glad because they had quiet, and he brought them to their desired haven. Let them thank the Lord for his steadfast love, for his wonderful works to the sons of men!”
St. Paul seems to have experienced something similar, whether at sea or in some other place:
“We do not want you to be ignorant, brethren, of the affliction we experienced in Asia; for we were so utterly, unbearably crushed that we despaired of life itself. Why, we felt that we had received the sentence of death; but that was to make us rely not on ourselves but on God who raises the dead; he delivered us from so deadly a peril, and he will deliver us; on him we have set our hope that he will deliver us again” (2 Cor. 1:8-10).
When you are able to imagine something of the paralyzing fear felt by the apostles, then contemplate Jesus’s question: “Why were you afraid? Have you no faith?” (Mk. 4:40)
There is one central affirmation involved in all faith in Jesus: that he is absolutely truthful and reliable. There can be no shadow of a doubt concerning the largest or the smallest exceptions — or else you do not believe in him as God. Thus, when he allows us to be “utterly, unbearably crushed,” yet ultimately “delivers us from so deadly a peril,” there is a purpose: “to make us rely not on ourselves but on God who raises the dead.” That is, he allows it in order to increase our faith.