الكافي- ط الاسلامية, volume 7, page 464

21. Ali ibn Ibrahim has narrated from his father from certain persons of his people whom he has mentioned who has narrated the following: “Al-Mutawakkil specified a vow and commitment that if he recovers he will give in charity kathir (a great deal of) assets. When he recovered, he asked the scholars of law about the limit of kathir (great deal) but they had different opinions. Certain ones among them said that it is a hundred thousand; others said that it is ten thousand, and they cited different things as proof in the matter. It all became confusing for him. One of his officers called Saf‘an said, ‘Why do you not send this black to ask him about it?’ Al-Mutawakkal asked, ‘Who do you mean thereby? Woe upon you!’ He replied, ‘I mean ibn al-Rida’.’ He asked, ‘Is he good in it?’ He (the officer) replied, ‘If he takes you out of this, you then must pay me so and so much; or you can whip me one hundred times.’ Al-Mutawakkal said, ‘I agree. O Ja‘far ibn Mahmud, go to him and ask him about the limit of kathir (a great deal of asset).’ Ja‘far ibn Mahmud went to abu al-Hassan, Ali ibn Muhammad, ‘Alayhim al-Salam, and asked him about the limit of al-Kathir (great deal of assets). He (the Imam) said, ‘It is eighty.’ Ja‘far asked, ‘O my master, he will ask me for a reason.’ Abu al-Hassan (a.s.), said, ‘Allah, most Majestic, most Glorious, says, ‘We have helped you in Mawatin al-Kathirah (in a great many places)’ and we counted them, they were eighty such places.’”

Translation: Muhammad Sarwar — attributed by Thaqalayn·The Arabic above is the original.