And when they came to Marah, they could not drink of the waters of Marah, for they were bitter: therefore the name of it was called Marah. And …

And the people murmured against Moses
For bringing them into a wilderne where they could find no water fit to drink;…

In the wilderness of Shur, the Israelites had no water. At Marah, they had water, but it was bitter, so they could not drink it. God can make bitte…