Similarly, if two men are knowledgeable in medicine, arithmetic, Islamic jurisprudence, grammar, or any other discipline, the one with greater mastery of that discipline is the more knowledgeable of the two; (* if they are equal in this respect, they are equal in knowledge. Neither becomes more knowledgeable because his father or his son (1) is more knowledgeable than the other man. The same applies to courage, generosity, asceticism, and religious devotion.
With this established, external merits carry no weight before Allah Most High *) (2), unless they contribute to an increase in inner virtues (3). In that case, excellence rests on those inner virtues (4). As for bodily virtues, they carry no weight unless they arise from virtue of the soul.
Thus, whoever prays, fasts, fights, and gives charity without a sincere intention gains no superiority thereby. What counts is the heart.
As reported in the Sahīh collections of al-Bukhārī and Muslim, the Prophet—may Allah bless him and grant him peace—said:
“Indeed, there is a piece of flesh in the body: when it is sound, the rest of the body is sound, and when it is corrupt, the rest of the body is corrupt. Indeed, it is the heart.” (5)
(1) N: yakūnu ibnahu aw abīhi (“his son or his father is”).
(2) The passage between the two asterisks is omitted in M.
(3) N, S, B: al-dākhila (“inner”).
(4) N, S, B: al-dākhila (“inner”).
(5) The hadith narrated by al-Nu‘mān ibn Bashīr—may Allah be pleased with him—is recorded in al-Bukhārī, 1/16 (Book of Faith, chapter on the merit of safeguarding one’s religion). Its wording is: “The lawful is clear, and the unlawful is clear. Between them are doubtful matters that many people do not know. Whoever avoids doubtful matters safeguards his religion and honour. Whoever falls into doubtful matters is like a shepherd grazing around a protected pasture, on the verge of entering it. Indeed, every king has a protected pasture; indeed, Allah’s protected pasture on His earth consists of the things He has forbidden. Indeed, there is a piece of flesh in the body: when it is sound, the entire body is sound, and when it is corrupt, the entire body is corrupt. Indeed, it is the heart.” The hadith also appears, with differences in wording, in Muslim, 3/1219–1220 (Book of Irrigation, chapter on taking what is lawful and avoiding doubtful matters); Sunan Ibn Mājah, 2/1318–1319 (Book of Tribulations, chapter on refraining when faced with doubtful matters); and al-Musnad (al-Halabī edition), 4/270–274.