A presentation of the passages from Allah’s Book and the Sunnah of His Messenger, may Allah bless him and grant him peace, that establish—or have been explained as establishing—and of the reports transmitted from the Companions, the Followers, and the learned imams of the religion after them, that faith increases through obedience and decreases through disobedience.

As for the explicit text of Allah’s Book, Allah, exalted is He, says ⦗961⦘: “The believers are only those who, when Allah is mentioned, their hearts tremble; when His verses are recited to them, they increase them in faith; and they put their trust in their Lord—those who establish prayer and spend from what We have provided for them. It is they who are truly believers. They will have ranks with their Lord, forgiveness, and a noble provision.” [al-Anfal: 3]

⦗962⦘ Allah, exalted is He, also says: “So it increased them in faith, and they said, ‘Allah is sufficient for us, and He is the best Disposer of affairs.’” [Al Imran: 173] He says: “That they may increase in faith along with their faith.” [al-Fath: 4] And He says: “Whenever a surah is revealed, some of them say, ‘Which of you has this increased in faith?’ As for those who believe, it increases them in faith, and they rejoice.” [al-Tawbah: 124] He also says: “Today I have perfected your religion for you, completed My favour upon you, and chosen Islam for you as your religion.” [al-Ma'idah: 3] And His words, “So that my heart may be at ease,” [al-Baqarah: 260] mean: “So that my faith may increase.”

It is also reported from the Prophet, may Allah bless him and grant him peace: “The believers most complete in faith are those with the best character.” In the hadith of intercession: “Bring forth whoever has a mustard seed of faith in his heart”; “No one who has in his heart the weight of a seed of faith will enter the Fire”; “Purification is half of faith”; and “Faith has seventy-odd branches.”

This view was also held by the following Companions: Umar ibn al-Khattab, Ali ibn Abi Talib, Abdullah ibn Masud, Muadh ibn Jabal, Abu al-Darda, Ibn Abbas, Ibn Umar, Ammar, Abu Hurayrah, Hudhayfah, Salman, Abdullah ibn Rawahah, Abu Umamah, Jundub ibn Abdullah al-Bajali ⦗963⦘, Umayr ibn Khumashah, and Aishah.

1599—It is reported from Abu Mulaykah: “I met many of the Companions of the Prophet, may Allah bless him and grant him peace, and not one of them died without fearing hypocrisy for himself.”