Narrated Ibrahim ibn Muhammad, one of the offspring of 'Ali ibn Abi Talib, told me:
“When 'Ali described Allah’s Messenger (Allah bless him and give him peace)— then he related the tradition in full—he said: 'Between his shoulders was the Seal of Prophethood, for he is the Seal of the Prophets'."
"I heard Allah’s Messenger (Allah bless him and give him peace)- and if I wished to kiss the seal between his shoulders, I would do so because of his nearness— say to Sa'd ibn Mu'adh on the day he died: “The Throne of the
All-Merciful was shaken on his account!”
Narrated Abu Zaid 'Amr ibn Akhtab al-Ansari told me:
“Allah’s Messenger (Allah bless him and give him peace) said to me: ‘O Abu Zaid, come close to me and stroke my back!’ I duly stroked his back, whereupon my fingers touched the Seal. I said: ‘What is the Seal?’ He said; ‘Intertwined hairs.’”