Musnad Abu Ya'la al-Mawsili 5:5

Zuhayr narrated to us, Ya'qub ibn Ibrahim narrated to us, my father narrated to us, from Ibn Ishaq, Yahya ibn 'Abbad ibn 'Abd Allah ibn al-Zubayr narrated to us, from his father, from 'Abd Allah ibn al-Zubayr, from al-Zubayr, who said: I heard the Messenger of Allah, peace and blessings of Allah be upon him, say on that day: "Talha has made [Paradise] obligatory [for himself] due to what he did for the Messenger of Allah." Ibn Ishaq said: On the day of Uhud, the Messenger of Allah, peace and blessings of Allah be upon him, rose toward a rock on the mountain to climb it. He had become heavy and was wearing two coats of mail. When he went to rise, he could not. Talha ibn 'Ubayd Allah sat beneath him, so he rose until he stood firmly upon it.