Al-Kāfi 2, narration 100

Translation

5. Ali ibn Ibrahim has narrated from Muhammad ibn ‘Isa from Yunus who has said the following: “I asked abu al-Hassan al-Rida (a.s.) about belief and Islam and he said, abu Ja’far (a.s.) has said the following: ‘There is Islam. Belief is one degree higher above Islam, and piety is one degree higher above belief. Certainty is by one degree higher above piety and nothing is distributed among people so little as certainty is.’ I then said, ‘What then is certainty?’ The Imam said, ‘It is trust in Allah, submission to Allah, accepting the decision of Allah and allowing Allah to be the person in charge of one’s affairs.’ I then said, ‘What then is the interpretation of that?’ The Imam said, ‘This is how abu Ja’far (a.s.) said it is.’”

Translation: Muhammad Sarwar — published with the edition, reproduced verbatim.