But the men marvelled, saying, What manner of man is this, that even the winds and the sea obey him!

People's New Testament

8:27 What manner of man? The words express astonishment at this new proof of his control, not only over demons and disease, but also over the winds and waves, which obeyed him at his word.

Matthew Henry's Concise Commentary

8:23-27 It is a comfort to those who go down to the sea in ships, and are often in perils there, to reflect that they have a Saviour to trust in and pray to, who knows what it is to be on the water, and to be in storms there. Those who are passing with Christ over the ocean of this world, must expect storms. His human nature, like to ours in every thing but sin, was wearied, and he slept at this time to try the faith of his disciples. They, in their fear, came to their Master. Thus is it in a soul; when lusts and temptations are swelling and raging, and God is, as it were, asleep to it, this brings it to the brink of despair. Then it cries for a word from his mouth, Lord Jesus, keep not silence to me, or I am undone. Many that have true faith, are weak in it. Christ's disciples are apt to be disquieted with fears in a stormy day; to torment themselves that things are bad with them, and with dismal thoughts that they will be worse. Great storms of doubt and fear in the soul, under the power of the spirit of bondage, sometimes end in a wonderful calm, created and spoken by the Spirit of adoption. They were astonished. They never saw a storm so turned at once into a perfect calm. He that can do this, can do any thing, which encourages confidence and comfort in him, in the most stormy day, within or without, Isa 26:4.