Albert Barnes' Notes on the Whole Bible - Job 41:7
Canst thou fill his skin with barbed irons? - Referring to its thickness and impenetrability. A common method of taking fish is by the spear; but it is here said that the leviathan could not be caught in this manner. The common method of taking the crocodile now is by shooting him; see the notes at Job 41:1. Nothing is more remarkable in the crocodile than the thick and impenetrable skin with which it is covered; and the description here will agree better with this animal than with any other.Or... read more
The Pulpit Commentary - Job 41:8
Lay thine hand upon him, remember the battle, do no more . This is again ironical, like Job 41:3-6 . "Only just put forth thy hand against him—bethink thee of war—do it once and no more.". The idea is that once will be enough. A man will not live to do it a second time. read more