Adam Clarke Bible Commentary
He maketh a path to shine after him - In certain states of the weather a rapid motion through the water disengages many sparks of phosphoric fire. I have seen this at sea; once particularly, on a fine clear night, with a good breeze, in a fast-sailing vessel, I leaned over the stern, and watched this phenomenon for hours. The wake of the vessel was like a stream of fire; millions of particles of fire were disengaged by the ship's swift motion through the water, nearly in the same way as by the electric cushion and cylinder; and all continued to be absorbed at a short distance from the vessel. Whether this phenomenon takes place in fresh water or in the Nile, I have had no opportunity of observing.
The deep to be hoary - By the frost and foam raised by the rapid passage of the animal through the water.
John Gill Bible Commentary
Upon the earth there is not his like,.... As to form and figure; in most creatures there is some likeness between those in the sea and on the land, as sea horses, calves, &c. but there is no likeness between a whale and any creature on earth; there is between the crocodile and the lizard; nor is any like the whale for the largeness of its bulk; the Targum is,
"his dominion is not on the earth,''
but on the sea, as Aben Ezra notes; but rather the sense is, there is no power on earth that he obeys and submits to, as the Tigurine version; though the meaning seems to be, that there is none like him, for what follows:
who is made without fear; yet this agrees not neither with the crocodile, which Aelianus (w) says is fearful; nor with the whale, which will make off and depart at the shoutings of men, blowing of trumpets, and making use of any tinkling instruments, at which it is frightened, as Strabo (x), Philostratus (y), and Olaus Magnus (z), relate. It is observed (a); of their valour, that if they see a man or a long boat, they go under water and run away; and are never known to endeavour to hurt any man, but when in danger; though a voyager (b) of our own says,
"we saw whales in Whale-sound, and lying aloft on the water, not fearing our ships, or aught else.''
The Targum is,
"he is made that he might not be broken;''
or bruised, as Bochart; as reptiles usually may, among whom the crocodile may be reckoned, because of its short legs; and yet is made with such a hard scaly skin, that it cannot be crushed, bruised, and broken. Aben Ezra observes that some say, the word "hu", that is, "he", is wanting, and should be supplied, "he", that is, "God, made him without fear"; or that he might not be bruised; wherefore Cocceius interprets the following words entirely of God.
(w) De Animal. l. 10. c. 24. (x) Geograph. l. 15. p. 499. (y) Vit. Apollon. l. 3. c. 16. (z) De Ritu Gent. Septent. l. 21. c. 3, 6. (a) Voyage to Spitzbergen, p. 153. (b) Baffin in the North-West Fox, p. 150.