Narrated to us Muhammad bin Hasan bin Ahmad bin Walid (r.a.) from Saad bin Abdullah from Ali Ibne Muhammad ar-Raazi, famous as Kulaini that he said: Narrated to me Muhammad bin Shazan bin Nuaim Nishapuri that he said:
“An amount of 480 dirhams collected with me from the money that was supposed to be paid to His Eminence, Qaim (a.t.f.s.). So I did not like sending it without rounding off the amount (to 500). Therefore I added 20 dirhams of my own and sent 500 dirhams to Muhammad bin Ja’far but I did not mention that 20 dirhams were from my side.
Thus Muhammad bin Ja’far received acknowledgment from the Holy Hidden Imam (a.s.) that he sent to me in turn. It was written on the receipt: Received 500 dirhams of which 20 were your own.”