Sahih al-Bukhari 190

Hadith text

Narrated As-Sa'ib bin Yazid:My aunt took me to the Prophet (ﷺ) and said, "O Allah's Messenger (ﷺ)! This son of my sister has got a disease in his legs." So he passed his hands on my head and prayed for Allah's blessings for me; then he performed ablution and I drank from the remaining water. I stood behind him and saw the seal of Prophethood between his shoulders, and it was like the "Zir-al-Hijla" (means the button of a small tent, but some said 'egg of a partridge.' etc)

As-Sa'ib bin Yazid bataate hain ke unki khala unhe Nabi ke paas le gayi aur kaha: "Ya Rasoolallah, meri bhen ke bete ke paon mein bimari hai." Nabi ne mere sar par haath phera aur meri barkat ki dua ki, phir wudu kiya aur main baqi paani piya. Main unke peechhe khada hua aur unke shoulders ke beech Nabuwwat ki mohar dekhi, jo ek chhote khaimay ke button jaisi (ya titar ke ande jaisi) thi.

Sahih al-Bukhari 190 · Book 4, Hadith 56