H 79 - Abdullah bin Ja’far Himyari has narrated from Muhammad bin Isa Yaqtini that he said
When people fell into discord with regard to the Imamate of Abul Hasan Imam Ridha (a.s), I collected the questions that were framed to gain confidence and certainty in his Imamate; and they totalled up to 15000, all of which the Imam replied.