Exodus 15:21-23

Amplified Bible, Classic Edition

²¹ And Miriam responded to them, Sing to the Lord, for He has triumphed gloriously and is highly exalted; the horse and his rider He has thrown into the sea.

²² Then Moses led Israel onward from the Red Sea and they went into the Wilderness of Shur; they went three days [thirty-three miles] in the wilderness and found no water.

²³ When they came to Marah, they could not drink its waters for they were bitter; therefore it was named Marah [bitterness].