Musnad Ahmad Hadith 20778

Abdullah bin Sarjis (may Allah be pleased with him) once said about himself that I presented myself in the service of the Prophet (ﷺ) and ate food with him. I said to him, "O Messenger of Allah, may Allah grant you forgiveness." The narrator says that I asked him, "Did the Prophet (ﷺ) also seek forgiveness for you?" He said, "Yes, and he also did so for you." Then he recited this verse: "And seek forgiveness for your faults and for the believing men and women." Then I saw the Seal of Prophethood between his two shoulders, which was on the corner of the left shoulder and was like a fist. He made a fist and showed it by gesture, and on the Seal of Prophethood there were raised moles like warts.