Sunan An-Nasa'i

Hadith #36

It was narrated from 'Abdullah bin Mughaffal that the Prophet (ﷺ) said:""None of you should urinate in the place where he bathes, for most Waswas (devilish whispers) [1] come from that."" [1] I.e., with regard to whether the urine has soiled his body or not