Salmos 18:11

(11) Secret place. — Better, veil. Comp. Jó 22:14; Lamentações 3:44. A better arrangement of the members of this verse is, He made darkness His veil round about Him; His tent He made of dark waters and black clouds. Literally, darkness of waters and blacknesses of clouds. (Comp. Salmos 97:2; Jó 36:29.) In Samuel, instead of “blacknesses” of clouds, the expression used is “bendings,” or “collectings,” and the parallelism is marred by the omission of “his veil.”

Always present to the Hebrew imagination, God is still invisible, veiled by thick clouds, and far withdrawn in His own ineffable brightness.
This verse gives suggestion of that momentary lull so common before the final fury of a storm bursts. In the Hebrew imagery Jehovah stays His winged car, and draws round Him, as if to take up His abode within them, thick curtains of cloud.

“We often see, against some storm,

A silence in the heavens, the rack stand still,
The bold winds speechless, and the orb below
As hush as death.” — SHAKSPEARE: Hamlet.