الكافي- ط الاسلامية, volume 1, page 11

3. Ahmad ibn ’Idris has narrated from Muhammad ibn ‘Abd al-Jabbar, from one of our people in a marfu’ manner that Abu 'Abdillah (al-Sadiq) (as) was asked, 'What is intellect (al-'Aql)?'. He said, ‘It is what someone worships ar-Rahman with and attains paradise.’ I then asked, 'What was the thing within Mu'awiya?'. He replied, ‘That was heinousness, that was devilry and it is similar to the intellect but it is not intellect.’

Translation: Muhammad Sarwar·Thaqalayn link·The Arabic above is the original.

4. Muhammad ibn Yahya has narrated from Ahmad ibn Muhammad ibn ‘Isa from ibn Faddal from al-Hassan ibn al-Jahm that he heard (Imam) al-Ridha (as) saying, “The friend of every person is his intellect and his enemy is ignorance.”

Translation: Muhammad Sarwar·Thaqalayn link·The Arabic above is the original.

5. It is narrated from him from Ahmad ibn Muhammad from ibn Faddal that al-Hassan ibn al-Juham said: “I told Abul Hasan (al-Ridha) (as), 'We know of a people who have love [for the Ahlul-bayt] but they do not have much determination [in understanding their imamate], they make such claims.' He then replied, 'They are not of the ones that Allah has admonished. Indeed Allah has said: Take heed, Oh people of vision.'" (59:2)

Translation: Muhammad Sarwar·Thaqalayn link·The Arabic above is the original.

6. Ahmad ibn Idris has narrated from Muhammad ibn Hassa’n from abu Muhammad al-Razi from Sayf ibn ‘Umayra from Ishaq ibn ‘Ammar that Abu ‘Abdillah (al-Sadiq) (as) said: “Whoever has intelligence has religion and whoever has religion enters paradise."

Translation: Muhammad Sarwar·Thaqalayn link·The Arabic above is the original.

7. A number of our people have narrated from Ahmad ibn Muhammad ibn Khalid from al-Hassan ibn Ali ibn Yaqtin from Muhammad ibn Sinan from Abul Jarud that Abu Ja‘far (al-Baqir) (as) said: “On the Day of Judgment, Allah will hold everyone accountable according to the degree of intelligence He had given them in their worldly life.”

Translation: Muhammad Sarwar·Thaqalayn link·The Arabic above is the original.

8. Ali ibn Muhammad ibn Abdullah reported from Ibrahim ibn Ishaq al-Ahmar, from Muhammad ibn Sulaiman al-Daylami, from his father, who said: I said to Abā ʿAbdillah al-Sadiq (as), "So-and-so is from his worship, religion, and virtue." He said, "What about his intellect?" I replied, "I do not know." He said, "Indeed, the reward is based on the measure of intellect. A man from the Children of Israel used to worship Allah on an island of the sea, green and lush, with plenty of trees and visible water. And an angel from the angels passed by him and said, 'O my Lord, show me the reward of Your servant.' Allah, the Exalted, showed him that. The angel then felt small in comparison and was inspired by Allah to accompany him. So the angel came to him in human form and said to him, 'Who are you?' He replied, 'I am a worshiper. I have heard of your location and your worship in this place, so I have come to worship Allah with you.' He was with him that day. When morning came, the angel said to him, 'Indeed, your place is pure and only suitable for worship.' The worshiper replied, 'This place has a defect.' The angel asked, 'What is it?' He said, 'Our Lord does not have livestock, so if He had a donkey, we would graze it in this location, for this grass would go to waste.' The angel responded, 'What does your Lord have to do with a donkey?' The worshiper said, 'If He had a donkey, this grass would not go to waste.' Allah then revealed to the angel, 'I reward him based on the measure of his intellect.'"

Translation: Muhammad Sarwar·Thaqalayn link·The Arabic above is the original.