Wherefore are we counted as beasts? - "Why are we treated in your remarks as if we had no sense, and were unworthy of sound argument in reply to what we say?" It is possible that there may be reference here to what Job said Job 12:7 - that even the beasts could give them information about God. But the general idea is, that Job had not treated their views with the attention which they deserved, but had regarded them as unworthy of notice.
And reputed vile - The word used here (טמה ṭâmâh) means to be unclean, or polluted; and the idea is, that Job regarded them as worthless or impious.

Counted as beasts - Thou treatest us as if we had neither reason nor understanding.

Wherefore are we counted as beasts,.... This seems to refer to Job 12:7; where Job sends them to the beasts, to get knowledge and instruction; and therefore it was concluded he reckoned them as such, and put them on a level with them, yea, made them inferior to them; or to Job 17:4; where they are represented as destitute of wisdom and understanding, and therefore it is supposed were counted by Job no other than as beasts. Man, by the fall, is indeed become like them, and some are more brutish than they, and all are brutish as to spiritual knowledge and understanding; and those that are most sensible of themselves are ready to acknowledge their ignorance, that they are more brutish than any, and especially are as a beast before God; and particularly with respect to knowledge of the methods of Providence, in regard to his dealings with the righteous and wicked; see Psalm 73:22; and which was the case in controversy between Job and his friends; but yet self-sufficient persons do not care to have their understandings in anything called in question, but like the Pharisees say, "are we blind also?" John 9:40; and take it very hard that they should be reckoned like beasts, void of understanding, when they are the people, and wisdom will die with them:
and reputed vile in your sight? as wicked and profligate persons, the most abandoned of mankind, such as are justly despised by good men, see Psalm 15:4; or "unclean" (h), filthy, polluted, and defiled, as all men are by nature, and as they are in all the powers and faculties of their souls; nor can they make themselves clean, their hearts or their hands; nothing short of the grace of God, and blood of Christ, can cleanse from sin; yet self-righteous persons think themselves clean and pure when they are not washed from their sins, and take it ill of others to be reputed unclean persons: or "shut" (i), stopped up, as the hearts of men are from God and Christ, and the true knowledge of them, and divine things, until opened by him who has the key of the house of David, and opens, and no man shuts; or "hidden" (k), referring to Job 17:4; having a covering over their hearts, and a vail over the eyes of their understandings, so that the things of Providence were hid from them, as sometimes the things of grace are from the wise and prudent; but to be thought that this was their case is resented by Bildad.
(h) "immundi", Drusius, Piscator, Michaelis; so Broughton. (i) "Clausi sumu", Montanus; "obturati sumus", Hebraei, in Mercer. (k) So the Targum.

beasts--alluding to what Job said (Job 12:7; so Isaiah 1:3).
vile--rather from a Hebrew root, "to stop up." "Stubborn," answering to the stupidity implied in the parallel first clause [UMBREIT]. Why should we give occasion by your empty speeches for our being mutually reputed, in the sight of Job and one another, as unintelligent? (Job 17:4, Job 17:10).

Beasts - Ignorant, and stupid men, Job 17:4, Job 17:10.