Those who give the Prophet’s statement its full, unrestricted scope hold that the two Sunnah rakʿahs of Fajr may not be prayed once the obligatory prayer has been called to commence—neither inside the mosque nor outside it.

Others restrict the prohibition to the mosque; according to them, one may offer the two rakʿahs outside the mosque provided he will not miss the prescribed prayer or any part of it.

For those who treat the wording as general, the rationale for the ban is simple: engaging in a supererogatory act diverts one from the obligation. Those who confine it to the mosque argue that the objection lies in two prayers being held simultaneously in a single place, thereby creating dissent from the imam. They cite the report in which Abū Salamah b. ʿAbd al-Raḥmān related:

“Some people heard the iqāmah and rose to pray. The Messenger of Allah—peace and blessings be upon him—came out to them and said, ‘Are two prayers being offered together?’ This occurred at the Dawn Prayer and concerned the two rakʿahs that precede it.”

Mālik and Abū Ḥanīfah differed only about the amount of the obligatory prayer that must be missed for the worshipper occupied with the Sunnah to forfeit the reward of congregational prayer, because they both considered congregational merit superior to that of the two rakʿahs.

• Whoever holds that missing a single rakʿah of the congregation nullifies its merit says: he may engage in the Sunnah as long as he will not miss one rakʿah of the prescribed prayer.

• Whoever holds that the merit remains as long as he catches one rakʿah of the obligation—invoking the Prophetic ḥadīth, “Whoever catches one rakʿah of the prayer has caught the prayer,” and applying it broadly, whether the delay was intentional or not—says: he may pray the two rakʿahs so long as he believes he will catch one rakʿah of the obligation.

Mālik—Allah knows best—applies that ḥadīth to someone who misses the prayer unintentionally; hence he judged that missing even one rakʿah causes the congregational merit to lapse.

Anyone who permits the two rakʿahs to be prayed in the mosque while the iqāmah is being given does so for one of two reasons: either he does not regard the relevant report as authentic, or the report never reached him. Abū Bakr ibn al-Mundhir said, “The report is in fact sound—the Prophet’s saying, peace and blessings be upon him, ‘When the prescribed prayer has begun, there is no prayer except the prescribed one.’” Abū ʿUmar ibn ʿAbd al-Barr likewise validated it, though permission to perform the two rakʿahs in that circumstance is related from Ibn Masʿūd.

The fourth issue concerns the time for making up the two rakʿahs when they have been missed until after the Dawn Prayer. One group maintained that they should be made up immediately after the obligatory Fajr; this is the position of ʿAṭāʾ and Ibn Jurayj. Another group said they should be made up after sunrise. Among them, some allotted only a brief window, while others granted a wider span, allowing the makeup from sunrise until the sun reaches its zenith but not thereafter.

Those who call for making them up are themselves of two stripes: some deem it recommended, while others consider it optional. The basic precedent for making them up is the Prophet’s own practice—peace and blessings be upon him—when he overslept and prayed them after sunrise.