The Boundaries of the Arabian Peninsula and the Status of Non-Muslims Within It
The scholars differed over the boundaries of the Arabian Peninsula. Al-Shafi'i (may Allah have mercy on him Almighty) holds that the Arabian Peninsula is [everything within] the entrances of the Red Sea and the Arabian Gulf — everything that is within the Red [Sea] and the Arab [Gulf] constitutes the Arabian Peninsula. Al-Shafi'i holds that Najran and its surroundings, and all of Yemen, are within the Arabian Peninsula — up to the borders of Syria and up to the borders of Iraq — all of it from the Arabian Peninsula.
And one group of scholars held that the Arabian Peninsula is only Makkah and Madinah. And another group of scholars held that it is only Makkah and Madinah. And alongside that — from the Arabian Peninsula. And the majority held that the Arabian Peninsula is Makkah, Madinah, and Najd — and what surrounds them. And this is the view of the bulk of scholars. And our boundary is Samira — what is beyond Samira is not from Najd but belongs to the Levant (al-Sham). And this is the view of the bulk of scholars. The proponents of this view argue that it was 'Umar (may Allah be pleased with him) who took charge of expelling the Christians and Jews from the Arabian Peninsula. And he expelled them to Tayma', which is about four hundred kilometres from Madinah. So [these places] are within the Red Sea and the Arabian Gulf. So they say: this is evidence that the intended meaning is not the Arabian [Peninsula] as geographically known — rather a specific known thing is intended — as a shar'i [religious-legal] demarcation.
And a group of scholars held that 'Umar (may Allah be pleased with him) [expelled them there] because that was what was practicable — not because Tayma was not from the Arabian Peninsula. And some of them said: no — because Tayma' belongs to the Levant — and the Levant was never part of the Arabian Peninsula. And they also cited some reports (athar) narrated that the Companions (may Allah be pleased with them) expelled the people of Najran — saying: this is evidence that the intended meaning of "expelling [non-Muslims from the Peninsula]" is beyond Makkah, Madinah, and Najd. But these reports narrated about the expulsion from Najran are all defective (ma'lulah). The reports narrated about the expulsion from Najran are all defective. Had they been sound, they would have been an explicit text on the matter.
Therefore, the view of the majority — which Hafiz Ibn Hajar chose in Al-Fath — is that the Arabian Peninsula is Makkah, Madinah, and what surrounds them. And the matter is one of [genuine] scholarly disagreement, because some scholars [treat it] as a geographical demarcation — and it is clear what the boundaries of the Arabian Peninsula are geographically: everything within the Arabian Gulf and the Red Sea — all of it constitutes the Arabian Peninsula — geographically. But the difficulty lies only in the action of 'Umar (may Allah be pleased with him): why did he expel them to Tayma', if this [place] is the Arabian Peninsula?