Riyad as-SalihinChapter 17Hadith 834
Full Sharh — Riyad as-Salihin 834
وعن سهل بن سعد قال: قال رسول الله صلى الله عليه وسلم: "من يضمن لي ما بين لحييه، وما بين رجليه أضمن له الجنة" ((متفق عليه)).
English Translation
Sahl bin Sa'd (May Allah be pleased with him) reported:: The Messenger of Allah (ﷺ) said, "Whosoever gives me a guarantee to safeguard what is between his jaws and what is between his legs, I shall guarantee him Jannah.".
Source
Riyad as-Salihin(رياض الصالحين)
The Book of the Prohibited actions
Hadith Number
834