His rows of scales are his pride, tightly sealed together.
God, having in the foregoing verses shown Job how unable he was to deal with the leviathan, here sets forth his own power in that massy mighty creature. Here is, I. God's sovereign dominion and independency laid down, Job 41:11. 1. That he is indebted to none of his creatures.
Commenting on Job 41:11-34
His scales are his pride, shut up together as with a close seal. This is notoriously true of the crocodile, whose back and tail are covered with scales, which are in a measure impenetrable and invincible: which all writers concerning it, and travellers that have seen it, agree in; See Gill on Eze 29:4; but the skin of the whale is smooth; the outward skin...
Rather, his "furrows of shields" (as "tubes," "channels," see on Job 40:18), are, &c., that is, the rows of scales, like shields covering him: he has seventeen such rows. shut up--firmly closed together. A musket ball cannot penetrate him, save in the eye, throat, and belly.