The monk was up and the river was down

The protagonists are facing a large river, difficult to cross:

The monk said “wait here” and he would really go further up and see if there is other possibilities to cross the river, I saw him going, and to me it appeared like the monk was up and the river was down but after a while…

It is clear that this is what the interpreter said. Could it be a rendition of a Tibetan idiom or turn of phrase?