Hadith 1 — Actions by Intentions

Imam al-Nawawī opens the Forty with a hadith reported on the authority of `Umar ibn al-Khaṭṭāb, in which the Prophet ﷺ said:

The hadith is reported in both Ṣaḥīḥ al-Bukhārī (the very first hadith of the collection) and Ṣaḥīḥ Muslim, with a chain that runs back through Yaḥyā ibn Saʿīd al-Anṣārī to Muḥammad ibn Ibrāhīm al-Taymī to ʿAlqamah ibn Waqqāṣ al-Laythī to ʿUmar.

The position of this hadith at the head of so many collections is deliberate. Imam al-Bukhārī placed it first because he held — as did many before him — that every action of the religion turns on what the heart intends by it. Worship without intention is empty; permitted action with the right intention becomes worship.

The hadith also establishes a structural principle in fiqh: the legal weight of an action is determined by its niyyah. A migration is judged by what one migrated for. A prayer is judged by whether the worshipper intended it, and which prayer they intended. A fast becomes worship by the intent that frames it.