When Imam Ali (a.s.) decided to move to Iraq and settle there, he handed his letters and testament to Umm Salamah, who in turn passed them over to Imam Hasan (a.s.) on his return to Madinah.
In a similar manner, when Imam Husain (a.s.) set out for Iraq, he too placed his letters and testament in the custody of Umm Salamah with instructions that she should hand them over to his eldest son whenever he sought them from her. After the martyrdom of Imam Husain (a.s.), Imam Sajjad (a.s.) returned to Madinah and she handed documents over to him.363
U’mar, the son of Umm Salamah, narrates:
“My mother said: Once, the Holy Prophet (s.a.w.), accompanied by Ali (a.s.), came to my house and asked for a sheepskin. After I had handed it to him, he wrote something on the sheepskin and returned it to me with the instruction: “Whoever seeks this trust from you after mentioning these signs, hand it over to him.”
As time passed, the Holy Prophet (s.a.w.) departed from this world. Time passed and Imam Ali (a.s.) became Caliph and still nobody came to claim this trust.
U’mar continues:
“On the day when the people pledged allegiance to Ali (a.s.), I was seated among them. As he stepped down from the pulpit, the Imam’s eyes fell on me whereupon he said: Seek permission from your mother for I wish to meet her.
I hurried to my mother and as soon as I informed her of Imam’s (a.s.) request, she announced that she had been waiting for that day.”
The Imam (a.s.) entered and asked Umm Salamah to hand him the trust which contained certain signs.My mother got up and took out a small chest from inside a larger one and handed it to him. Then, she turned to me and advised: “Do not forsake Ali (a.s.), for none other than him is the rightful Imam after the Holy Prophet (s.a.w.).” ( Payghambar Wa Yaaraan, vol. 1, pg. 275; Bihaar al-Anwaar vol. 6, pg. 942.)