Ahmad ibn Hanbal said: “Wakī‘ narrated to us, from Sharīk, from Hilāl, from ‘Abd Allāh ibn ‘Ukaym, who said: ‘I heard Ibn Mas‘ūd say in his supplication: “O Allah, increase us in faith, certainty and understanding.”’”

Sufyān al-Thawrī narrated from Jāmi‘ ibn Shaddād, from al-Aswad ibn Hilāl, who said: “Mu‘ādh ibn Jabal used to say to a man: ‘Sit with us and let us strengthen our faith by remembering Allah Most High.’”

Abū al-Yamān narrated: “Safwān narrated to us, from Shurayh ibn ‘Ubayd, that ‘Abd Allāh ibn Rawāhah would take one of his companions by the hand and say: ‘Come, let us strengthen our faith for a while, for we are in a gathering of remembrance.’” The Companions affirmed this increase after the Prophet’s death, may Allah bless him and grant him peace, and after the entire Quran had been revealed.

It is authentically reported that ‘Ammār ibn Yāsir said: “Whoever possesses three qualities has attained completeness of faith: being fair even at one’s own expense, spending despite poverty, and offering the greeting of peace to the scholar.” Al-Bukhārī cited this in his Sahīh.

Jundub ibn ‘Abd Allāh, Ibn ‘Umar and others said: “We learned faith, then we learned the Quran, and so our faith increased.” Reports concerning this are numerous. Authors who have written on this subject have transmitted them from the Companions and the Successors in many well-known books.

Mālik ibn Dīnār said: “Faith first appears in the heart weak and small, like a tender plant. If its possessor tends it, watering it with beneficial knowledge and righteous deeds, and removing the weeds and whatever weakens and saps it, it will soon grow or increase, developing roots, branches, fruit and shade without limit, until it becomes like mountains. But if its possessor neglects it and fails to tend it, a goat may come and pluck it out, or a child may carry it away, or he may let weeds proliferate around it, weakening it, destroying it or causing it to wither. Such is faith.”