石いしに漱くちすすぎ流ながれに枕まくらす

Idiom

1to refuse stubbornly to admit one is wrong ; to rinse one's mouth with a rock and rest one's head in a river Translated by Jiyomi

expressions (phrases, clauses, etc.) · su verb - precursor to the modern suru

JMdict entry 2141270. Source and licence.