Wilt thou hunt the prey for the lion? - The appeal here is to the instincts with which God has endowed animals, and to the fact that he had so made them that they would secure their own food. He asks Job whether he would undertake to do what the lion did by instinct in finding his food, and by his power and skill in seizing his prey. There was a wise adaptation of the lion for this purpose which man could neither originate nor explain.
Or fill the appetite of the young lions - Margin, as in Hebrew "life." The word life is used here for hunger, as the appetite is necessarily connected with the preservation of life. The meaning here is, "Wouldst thou undertake to supply his needs? It is done by laws, and in a manner which thou canst not explain. There are in the arrangement by which it is accomplished marks of wisdom which far surpass the skill of man to originate, and the instinct and power by which it is done are proof of the supremacy of the Most High." No one can study the subject of the instincts of animals, or become in the least acquainted with Natural History, without finding every where traces of the wisdom and goodness of God.

Wilt thou hunt the prey for the lion? - Rather the lioness, or strong lion. Hast thou his instinct? Dost thou know the habits and haunts of such animals as he seeks for his food? Thou hast neither his strength, his instinct nor his cunning. In the best Hebrew Bibles, the thirty-ninth chapter begins with this verse, and begins properly, as a new subject now commences, relating to the natural history of the earth, or the animal kingdom; as the preceding chapter does to astronomy and meteorology.

Wilt (a) thou hunt the prey for the lion? or fill the appetite of the young lions,
(a) After he had declared God's works in the heavens, he shows his marvellous providence in earth, even toward the brute beasts.

Wilt thou hunt the prey for the lion?.... From meteors the Lord passes to animals, beasts, and birds, wherefore some here begin the thirty ninth chapter, which only treats of such; and he begins with the lion, the strongest among beasts, and most fierce; cruel, and voracious; and asks, who hunts his prey for him? Not man, who cannot; and if he could, durst not: but the Lord does; and, according to some writers (x), he has provided a small creature, between a fox and a wolf, called a jackal; which goes before the lion, and hunts the prey for him. And could this be understood particularly of the old lion, as Cocceius and others, naturalists (y) observe, that young lions hunt for the old ones, when they are not able to go in search of prey; and when they have got it, either bring it to them, or call them to partake of it with them;
or fill the appetite of the young lions, whose appetite is sharp and keen, and requires a great deal to fill it, and especially to satisfy a great many of them; herds of them, as Mr. Broughton renders the word, and which signifies a company; see Psalm 68:30. Men cannot feed them, but God can and does; there being some ends in Providence to be answered thereby, see Psalm 104:21; see also Psalm 34:8.
(x) Thevenot's Travels, part 2. c. 13. (y) Aelian. de Animal. l. 9. c. 1.

At Job 38:39-39:30, the instincts of animals. Is it thou that givest it the instinct to hunt its prey? (Psalm 104:21).
appetite--literally, "life," which depends on the appetite" (Job 33:20).

39 Dost thou hunt for the prey of the lioness
And still the desire of the young lions,
40 When they couch in the dens,
Sit in the thicket lying in wait for prey?
41 Who provideth for the raven its food,
When its young ones cry to God,
They wander about without food?
On the wealth of the Old Testament language in names for the lion, vid., on Job 4:10. לביא can be used of the lioness; the more exact name of the lioness is לביּה, for לביא is = לבי, whence לבאים, lions, and לבאות, lionesses. The lioness is mentioned first, because she has to provide for her young ones (גּוּרים); then the lions that are still young, but yet are left to themselves, כּפירים. The phrase מלּא חיּה (comp. חיּה of life that needs nourishment, Job 33:20) is equivalent to מלּא נפשׁ, Proverbs 6:30 (Psychol. S. 204 ad fin.). The book of Psalm here furnishes parallels to every word: comp. on Job 38:39, Psalm 104:21; on ישׁחוּ, Psalm 10:10;
(Note: The Semitic is rich in such words as describe the couching posture of beasts of prey lying in wait for their prey, which then in general signify to lie in wait, lurk, wait (רצד, רבץ, Arab. rbṣ, lbd, wkkd); Arab. q‛d lh, subsedit ei, i.e., insidiatus est ei, which corresponds to ישׁבו, Job 38:40, also belongs here, comp. Psalter, i. 500 note.)
on מעונות, lustra, Psalm 104:22 (compared on Job 37:8 already); on סכּה, סך, which is used just in the same way, Psalm 10:9; Jeremiah 25:38. The picture of the crying ravens has its parallel in Psalm 147:9. כּי, quum, is followed by the fut. in the signif. of the praes., as Psalm 11:3. As here, in the Sermon on the Mount in Luke 12:24 the ravens, which by their hoarse croaking make themselves most observed everywhere among birds that seek their food, are mentioned instead of the fowls of heaven.

Hunt - Is it by thy care that the lions who live in desert places are furnished with necessary provisions? This is another wonderful work of God.