[Machine] Narrated Anas bin Malik:

The Prophet ﷺ said, "Do you not see those who commit illegal sexual intercourse, theft and drink alcohol, do you not condemn and pass verdict upon them (according to the Islamic law)?"

The companions replied, "Allah and His Apostle know better."

Thereupon the Prophet ﷺ said, "There are these filthy practices which people tolerate, but there lies within them severe punishment. Shall I not inform you of the greatest of the major sins?"

We said, "Yes, O Allah's Messenger ﷺ !"

He said, "Polytheism is to associate partners with Allah.

Then he recited: 'And whoever associates others with Allah has certainly fabricated a tremendous sin.' (Quran 4:48)

"And disobedience to parents."

He said, "Should I inform you of the greatest of the major sins?"

We said, "Yes, O Allah's Messenger ﷺ !"

He said, "False statement and false testimony."

He then sat up after he had been reclining and said, "Shall I tell you of the biggest lies? It is the false witness."

He continued to repeat it until we wished he would stop.

It was reported that Ibn 'Abbas said, "Whatever Allah's Messenger ﷺ prohibited then it is a major sin."  

أَنَّ نَبِيَّ اللهِ ﷺ قَالَ «أَرَأَيْتُمُ الزَّانِي وَالسَّارِقَ وَشَارِبَ الْخَمْرِ مَا تَقُولُونَ فِيهِمْ؟» قَالُوا اللهُ وَرَسُولُهُ أَعْلَمُ قَالَ «هُنَّ فَوَاحِشُ وَفِيهِنَّ عُقُوبَةٌ أَلَا أُنَبِّئُكُمْ مَا أَكْبَرُ الْكَبَائِرِ؟ الْإِشْرَاكُ بِاللهِ» ثُمَّ قَرَأَ {وَمَنْ يُشْرِكْ بِاللهِ فَقَدِ افْتَرَى إِثْمًا عَظِيمًا } وَعُقُوقُ الْوَالِدَيْنِ ثُمَّ قَالَ {اشْكُرْ لِي وَلِوَالِدَيْكَ إِلَيَّ الْمَصِيرُ} وَكَانَ مُتَّكِئًا فَاحْتَفَزَ فَقَالَ «أَلَا وَقَوْلُ الزُّورِ» وَقَالَ ابْنُ عَبَّاسٍ كُلُّ مَا نَهَى الله عَنْهُ فَهُوَ كَبِيرَةٌ