Who can number the clouds? - The word here rendered “clouds” (שׁחקים shachaqiym) is applied to the clouds as made up of “small particles” - as if they were composed of fine dust, and hence, the word number is applied to them, not as meaning that the clouds themselves were innumerable, but that no one could estimate the number of particles which enter into their formation.
In wisdom - By his wisdom. Who has sufficient intelligence to do it?
Or who can stay the bottles of heaven? - Margin, as in Hebrew “cause to lie down.” The clouds are here compared with bottles, as if they held the water in the same manner; compare the notes at Job 26:8. The word rendered “stay” in the text, and in the margin “cause to lie down,” is rendered by Umbreit, “pour out,” from an Arabic signification of the word. Gesenius supposes that the meaning to “pour out” is derived from the idea of “causing to lie down,” from the fact that a bottle or vessel was made to lie down or was inclined to one side when its contents were poured out. This explanation seems probable, though there is no other place in the Hebrew where the word is used in this signification. The sense of pouring out agrees well with the connection.