Kutoka 15 : 23 Exodus chapter 15 verse 23

Walipofika mahali palipoitwa Mara hawakupata kuyanywa yale maji ya Mara, kwa kuwa yalikuwa machungu; kwa ajili ya hayo jina lake likaitwa Mara.
soma Mlango wa 15

When they came to Marah, they couldn't drink from the waters of Marah, for they were bitter. Therefore the name of it was called Marah.{Marah means bitter.}