Sūrah Al-Inshiqāq The Sundering

Al-Qurṭubī uses this surah's sajdah verse "and when the Qurʾān is recited to them, they do not prostrate" (verse 21) as an occasion to survey the complete school-level disagreement on sajdah tilāwah verse counts. The verse itself condemns those who refuse to prostrate, establishing a strong moral argument for prostrating at all recognized sajdah locations, regardless of whether one's school classifies it as wājib or sunnah.

Al-Qurṭubī applies the uṣūl principle of ijtihād fī taḥdīd al-wājib: the scholars did not have a single complete list of sahīh (authentic) hadith naming every sajdah verse; they applied ijtihād to the available evidence, resulting in the 11/14/15 disagreement. The agreement on Al-Inshiqāq 21 shows that strong consensus exists on core verses, while disagreement clusters around a few contested locations. Al-Qurṭubī's position is that performing prostration at all 15 locations is safe and recommended avoiding the prostration at a location that some schools include risks omitting a wājib act.

• Al-Inshiqāq 21 is included in all four school sajdah verse lists agreement here contrasts with the few contested verses that produce the 11/14/15 count difference.
• Total sajdah verse counts: Mālikī 11, Ḥanafī and Shāfiʿī 14, Ḥanbalī 15 the disagreement is on a few specific verses, not on the concept itself.
• Al-Qurṭubī's recommendation: prostrate at all 15 locations to avoid missing any wājib prostration the safer approach when schools disagree is to follow the most inclusive count.
• The verse's condemnation of refusing to prostrate establishes that the moral weight of sajdah tilāwah exceeds its formal legal classification as wājib or sunnah.
• Ijtihād fī taḥdīd al-wājib: scholars applied ijtihād to available evidence on sajdah verses; the disagreement is legitimate and does not indicate error on either side.