أَنَّ  الكَبِيرَةَ مَا رُتِّبَتْ عَلَيْهِ عُقُوبَةً خَاصَّةً…

وَمَا نَهِيَ عَنْهُ فَقَطْ وَلَمْ يُعَيِّنْ لَهُ عُقُوبَةً خَاصَّةً فَهُوَ صَغِيرَة  

A major sin is whatever has a specific punishment as a consequence [of that action]. Whatever has been prohibited but for which there has not been particularised a specific punishment, then it is a lesser sin.

(From the Explanation of Safaareeniyyah of Shaykh al Uthaymeen)

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