Job 6:5

Doth the wild ass bray when he hath grass? or loweth the ox over his fodder?

Wild ass bray. Neither wild animals, as the wild donkey, nor tame animals, as the ox, are dissatisfied when well supplied with food. The braying of the one and the lowing of the other prove distress and lack of palatable food. So, Job argues, if he complains, it is not without cause-namely, his pains, which are as it were disgusting food which God feeds him with (end of Job 6:7). But he should have remembered, a rational being should evince a better spirit than the brute.