Now when they came to Marah, they could not drink the waters of Marah, for they were bitter. Therefore the name of it was called Marah.
Exodus 15:23
Surrounding context
15:22 So Moses brought Israel from the Red Sea; then they went out into the Wilderness of Shur. And they went three days in the wilderness and found no water.
15:23 Now when they came to Marah, they could not drink the waters of Marah, for they were bitter. Therefore the name of it was called Marah.
15:24 And the people complained against Moses, saying, "What shall we drink?"