Matthew Poole and continuators on Psalms 104:21

21 The young lions roar after their prey , and seek their meat from God .

Which can no more subsist without Divine Providence than those which are most old and decrepit.

They roar when they come within sight and reach of their prey, as Naturalists observe: whereby this place may be reconciled with Amos 3. 4.

This is a figurative and Poetical expression: their roaring is a kind of natural Prayer to God for relief, as the cryes of Infants are a kind of Prayers to their Mothers for the Breast. And this is justly noted as an act of Gods special Providence, because the Lions are very ravenous and need much prey, and also are dull in their scent, and so difficulty find it, and slow in their motion, and unable to reach it: and therefore God hath provided another Creature, of quicker sence and motion, which is usually confederate with them, and procures prey for them, partaking of it with or after them.

Marginal references: Job 38. 39.