Hadithcore
Bulugh al-Maram, 113

Narrated Abu Huraira (rad) regarding the story of Thumama bin Uthal when he embraced Islam:

The Prophet (ﷺ) ordered him to take a bath. [Narrated by Abdur-Razzaq]

وَعَنْ أَبِي هُرَيْرَةَ ‏- رضى الله عنه ‏- { ‏-فِي قِصَّةِ ثُمَامَةَ بْنِ أُثَالٍ, عِنْدَمَا أَسْلَم‏- وَأَمَرَهُ اَلنَّبِيُّ ‏- صلى الله عليه وسلم ‏-أَنْ يَغْتَسِلَ } رَوَاهُ عَبْدُ اَلرَّزَّاق ِ [1]‏ .‏

References2 variants
In-Book Reference
Book 1, Hadith 136
English Reference
Book 1, Hadith 121