ما حجة من منع اقتداء المفترض بالمتنفل من الأحناف والمالكية مع ورود حديث معاذ؟

The jurists differed regarding the validity of the obligatory prayer performed behind someone praying a supererogatory prayer, and the supererogatory prayer performed behind someone praying an obligatory prayer. The Shafi'is held it to be valid, while Al-Hasan al-Basri and Az-Zuhri, and one narration from Malik, prohibited it. Furthermore, Ath-Thawri and Abu Hanifah prohibited performing an obligatory prayer behind someone praying a supererogatory prayer or another obligatory prayer, but permitted performing a supererogatory prayer behind someone praying an obligatory prayer. Those who prohibited it cited the apparent generality of the prohibition against differing from the Imam.