Exodus 15:22–24

22 So Moses brought Israel from the Red sea, and they went out into the wilderness of Shur; and they went three days in the wilderness, and found no water. 23 And when they came to Marahc, they could not drink of the waters of Marah, for they were bitter: therefore the name of it was called Marah. 24 And the people murmured against Moses, saying, What shall we drink?