Zakariyyah b. Adam (r.a.) narrates: One day, I was in the presence of Imam Ali al-Reza (a.s.) when his son, Imam Muhammad al-Jawad, who was less than four years old, was brought to him. When he was brought in, he struck his palms on the ground and raised his head towards the heavens and remained engrossed in deep thought for a long time.
Seeing this, Imam al-Reza (asked him) – May I be your ransom! What are you thinking about?
Imam al-Jawad (a.s.) replied: I am engrossed in thought regarding the sufferings that befell my mother, Fatemah (s.a.). By Allah! I will bring out those two men from their graves and burn them and then scatter their ashes into the seas.
Hearing this, Imam al-Reza (a.s.) asked his son to be brought closer to him and then he kissed him on his forehead and said, ‘May my parents be your ransom! You are worthy for this affair (Imamat).’
Kitaab al-Dalaael p 212 Behaar al-Anwaar v 50 p 59 Madinah al-Ma'aajiz v 7 p 325