John Trapp on Job 36:30

Verſe 30. Behold, he ſpreadeth his light upon it] That is, his fair weather, clearing up the cloudy sky, as ſome expound it: Or, us others, his lighting ſhot forth every way, Pſal. 18.13, 15. & 144.6. Or the ſun-beams ſpread upon the ſea, and drawing up vapours; unde mare hoc loco nubium radix dicitur, ſaith Brentius, whence the ſea is here called the root of the clouds: or the ſurface of the ſea is called the root of it, in regard of the wandring waves which are cut in ſunder, after the manner of roots; ſo ſaith Vatablus. Thoſe that by light here underſtand lightnings ſay, that God maketh them dart ſo abundantly through the waters of the ſea, that they do as it were cover all the bottom of it.