Albert Barnes Commentary Exodus 17:6

"Behold, I will stand before thee there upon the rock in Horeb; and thou shalt smite the rock, and there shall come water out of it, that the people may drink. And Moses did so in the sight of the elders of Israel." — Exodus 17:6 (ASV)

The rock in Horeb - (a rock situated, according to Arab tradition, in Wady Feiran. Horeb was a name given to the whole desert of Sinai and subsequently attached to the mountain. Palmer).

It is questioned whether the water thus supplied ceased with the immediate occasion; see (1 Corinthians 10:4), the general meaning of which appears to be that their needs were ever supplied from Him, of whom the rock was but a symbol, and who accompanied them in all their wanderings.