Abu Hashim Ja’fari says:
I went to Imam al-Jawad (a) to give the letters of some companions to him. But I saw that the letters were anonymous, so I became worried what to say to Imam (a).
But, Imam (a) took one of the letters and said, “This is the letter of Ziyad, son of Shabat.”
He took the second letter and said, “This is the letter of Muhammad, son of Abu Hamza.”
He proceeded mentioning the names of the senders of the next letters.
I was surprised. Imam al-Jawad (a) looked at me and smiled.
Source:
Bihar al-Anwar, vol. 50, p. 41, Hadith no. 4.