The Hadith
Al-Nuʿman ibn Bashir (may Allah be pleased with him) said:
“I heard the Messenger of Allah say:
‘Indeed the lawful is clear and the unlawful is clear, and between them are doubtful matters which many people do not know. Whoever avoids the doubtful matters protects his religion and his honor. And whoever falls into doubtful matters falls into the unlawful, like a shepherd who grazes his flock around a sanctuary and is likely to enter it.
Indeed every king has a sanctuary, and indeed the sanctuary of Allah is His prohibitions.
Indeed in the body there is a piece of flesh; if it is sound the whole body is sound, and if it is corrupt the whole body is corrupt. Indeed it is the heart.’”
Reference
Reported by al-Bukhari and Muslim.
Explanation (From Shaykh Salih al-Fawzan)
In this hadith the Prophet clarified the ruling of matters in the religion by dividing them into three categories: lawful matters, unlawful matters, and doubtful matters.
The Prophet said:
“The lawful is clear and the unlawful is clear.”
This means that what Allah has permitted is clear and known, and what Allah has prohibited is also clear and known.
Between these two categories are doubtful matters which many people do not know. These are matters whose ruling is not clear to many people, even though the scholars may know their ruling based upon evidence.
Because of this, the Prophet encouraged the Muslim to avoid doubtful matters. Whoever stays away from these doubtful matters protects his religion from falling into what is unlawful and protects his honor from blame and suspicion.
However, the one who becomes careless regarding doubtful matters may eventually fall into the unlawful. For this reason the Prophet gave an example of a shepherd who grazes his animals near a protected sanctuary. If the animals graze close to the boundary, they are likely to enter it.
Likewise, a person who approaches doubtful matters is in danger of falling into what Allah has prohibited.
The Prophet then said:
“Indeed every king has a sanctuary.”
This refers to land that is protected and restricted by the ruler so that others cannot enter it.
Then the Prophet said:
“Indeed the sanctuary of Allah is His prohibitions.”
This means that the matters Allah has forbidden are boundaries that must not be violated.
The hadith concludes with an important principle concerning the heart. The Prophet explained that within the body there is a piece of flesh which, if it is sound, the entire body becomes sound, and if it becomes corrupt, the entire body becomes corrupt.
That piece of flesh is the heart.
This shows that the heart is the foundation of a person’s actions. When the heart is righteous and upright, the actions of the limbs become righteous. When the heart becomes corrupt, the actions also become corrupt.
References
The Explanation of Imam an-Nawawi’s 40 Hadith: Shaykh Salih al-Fawzan. Dar Makkah International.
Verified on 2026-10-21 against: The Explanation of Imam an-Nawawi’s 40 Hadith (Shaykh Salih al-Fawzan), Hadith 6.