Matthew Poole and continuators on Job 39:19

19. Hast thou given the horse strength ? hast thou clothed his neck with thunder ?

Either strength of body: or rather courage and generous confidence, for which the Horse is highly commended.

i. e. With snorting and neighing; in the making of which found the Neck, in regard of the Throat which is within it, and a part of it, is a principal instrument: which noise may not unfitly be called thunder, because of the great vehemency, and rage wherewith it is attended, and the great terrour which it causeth, especially in War and Battel, of which see Ier. 8. 16. and compare 1 Sam. 12. 17, 18. where this very term of thundring is ascribed to a far lower and less terrible noise. Nor is this, as some alledge, an improper speech, because this thunder or neighing is rather clothed with the Neck, as being within it, than the Neck with it; for nothing is more common in Scripture than to say that men are clothed with righteousness, humility, and other graces, which yet are in strictness of speech within the man, and not he within them. But because this word, in this form, is not elsewhere extant, some render it otherwise, with a mane, with a thick, and full, and deep mane, as the phrase of being clothed with it implies. For this is mentioned by all Writers of Horses, as a notable mark of a generous Horse; which therefore they conceive would not be omitted here where so many several properties and excellencies are described. And the Verb Raam, whence this comes, in the Syriack Language signifies not onely to thunder, but also to be high or lofty: which fitly agrees to the mane which is in the highest part of the Horse.