Musnad Ahmad 21:21

Abu Sa’id narrated to us, Qays ibn al-Rabi’ narrated to us, ‘Abdullah ibn Abi al-Safar narrated to me, from Ibn Sharhabil, from Ibn ‘Abbas, from al-‘Abbas, who said: I entered upon the Messenger of Allah, may Allah bless him and grant him peace, while his wives were with him. They veiled themselves from me, except Maymunah. He said: "There shall not remain anyone in the house who witnessed the *ludd* (forced medication) except that he is given *ludd*, except that my right hand did not afflict al-‘Abbas." Then he said: "Command Abu Bakr to lead the people in prayer." ‘Aishah said to Hafsah: "Tell him that Abu Bakr is a man who, when he stands in your place, weeps." He said: "Command Abu Bakr to lead the people in prayer." So he stood and prayed. Then the Prophet, may Allah bless him and grant him peace, felt a lightness, so he came. Abu Bakr, may Allah be pleased with him, retreated and wanted to step back, but he (the Prophet) sat beside him, then he recited.