Job 37:18

Hast thou with him spread out the sky?
&c.] Wast thou concerned with him at the first spreading out of the sky? wast thou an assistant to him in it? did he not spread it as a curtain or canopy about himself, without the help of another? verily he did; see ( Job 9:8 ) ( Isaiah 44:24 ) ;

[which] is strong:
for though it seems a fluid and thin, is very firm and strong, as appears by what it bears, and are contained in it; and therefore is called "the firmament of his power", ( Psalms 150:1 ) ;

[and] as a molten looking glass;
clear and transparent, like the looking glasses of the women, made of molten brass, ( Exodus 38:8 ) ; and firm and permanent ^F21; and a glass this is in which the glory of God, and his divine perfections, is to be seen; and is one of the wondrous works of God, made for the display of his own glory, and the benefit of men, ( Psalms 19:1 ) . Or this may respect the spreading out a clear serene sky, and smoothing it after it has been covered and ruffled with storms and tempests; which is such a wonderful work of God, that man has no hand in.