Job 6:15

My brethren have dealt deceitfully as a brook,.... Meaning his three friends, represented by Eliphaz, who were of the same sentiments with him, and behaved towards Job as he did: these were his brethren not by birth by blood nor by country, but by the profession of the same religion of the one true and living God in opposition to the idolatrous people among whom they dwelt; and this their relation to him is an aggravation of their perfidy and treachery, unfaithfulness and deceit, by which is meant their balking and disappointing him in his expectations; when they came to visit him as friends, he might reasonably expect they came to condole and sympathize with him, and comfort him; but, instead of this they reproached him and grieved him, and were miserable comforters of him; and this he illustrates by the simile of a "brook", which he enlarges upon in the following verses: these friends and brethren of his he compares to a "brook", not that was fed by a spring which continues, but filled with falls of water and melting snows from the hills, with which it is swelled, and looks like a large river for a while, but when these fail it is soon gone; hereby representing his friends in his state of prosperity, who looked big, and promised long and lasting friendship, but proved, in time of adversity, unfaithful and deceitful; and so it denotes the fickleness and inconstancy of their friendship:[and] as the stream of brooks they pass away: or, "pass by" , as a stream of water, fed by many brooks, or flows of water like unto many brooks, which run with great rapidity and force, and are quickly gone and seen no more; thus his friends, as such, passed by him, and were of no use to him any more than the priest and Levite were to the man that fell among thieves, Lu 10:30.