Shall vain words? - Margin, As in Hebrew words of wind; that is, words which were devoid of thought-light, trifling. This is a retort on Eliphaz. He had charged Job Job 15:2-3 with uttering only such words. Such forms of expression are common in the East. “His promise, it is only wind.” “Breath, breath: all breath.” Roberts.
Or what emboldeneth thee? - “What provokes or irritates thee, that thou dost answer in this manner? What have I said, that has given occasion to such a speech - a speech so severe and unkind?” The Syriac reads this, “do not afflict me any more with speeches; for if you speak any more, I will not answer you.”