Which are blackish by reason of the ice
When frozen over, they look of a blackish colour, and is what is called a black frost; and these either describe Job and his domestics, as some F8 think whom Eliphaz and his two friends compared to the above streams water passed away from, or passed by and neglected, and showed no friendship to; who were in black, mournful and rueful circumstances, through the severe hand of God upon them. The word is rendered, "those which mourn", ( Job 5:11 ) ; or rather the friends of Job compared to foul and troubled waters frozen over which cannot be so well discerned, or which were black through being frozen, and which describes the inward frame of their minds the foulness of their spirits the blackness of their hearts, though they outwardly appeared otherwise, as follows:
[and] wherein the snow is hid;
or "on whom the snow" falling, and lying on heaps, "hides" F9, or covers; so Job's friends, according to this account, were, though black within as a black frost yet white without as snow; they appeared, in their looks and words at first as candid, kind, and generous, but proved the reverse.
The Brenton translation of the Septuagint is in the public domain.