"While Imām ‘Ali (alayhi salām) was sitting with Ruhbah in Kufa, surrounded by a group, a man stood up and said: ‘ Commander of the Believers, you are in this great position at which Allāh has placed you while your father is suffering in hell.
‘ The Imām replied, saying: Be silent. May Allāh disfigure your mouth. By the One Who sent Muhammad (salla llāhu ʿalayhi wa-alehe wa-sallam) with the truth, if my father intercedes for every sinner on the face of the earth, Allāh would accept his intercession."
[Reference: al-Ihtijaj, by al-Tabarsi, v1, p341]