Bid'ah (heresy)

وَلَا تَقُولُوا۟ لِمَا تَصِفُ أَلْسِنَتُكُمُ ٱلْكَذِبَ هَٰذَا حَلَٰلٌۭ وَهَٰذَا حَرَامٌۭ لِّتَفْتَرُوا۟ عَلَى ٱللَّهِ ٱلْكَذِبَ ۚ إِنَّ ٱلَّذِينَ يَفْتَرُونَ عَلَى ٱللَّهِ ٱلْكَذِبَ لَا يُفْلِحُونَ

But say not - for any false thing that your tongues may put forth,- "This is lawful, and this is forbidden," so as to ascribe false things to Allah. For those who ascribe false things to Allah, will never prosper.

ثُمَّ قَفَّيْنَا عَلَىٰٓ ءَاثَٰرِهِم بِرُسُلِنَا وَقَفَّيْنَا بِعِيسَى ٱبْنِ مَرْيَمَ وَءَاتَيْنَٰهُ ٱلْإِنجِيلَ وَجَعَلْنَا فِى قُلُوبِ ٱلَّذِينَ ٱتَّبَعُوهُ رَأْفَةًۭ وَرَحْمَةًۭ وَرَهْبَانِيَّةً ٱبْتَدَعُوهَا مَا كَتَبْنَٰهَا عَلَيْهِمْ إِلَّا ٱبْتِغَآءَ رِضْوَٰنِ ٱللَّهِ فَمَا رَعَوْهَا حَقَّ رِعَايَتِهَا ۖ فَـَٔاتَيْنَا ٱلَّذِينَ ءَامَنُوا۟ مِنْهُمْ أَجْرَهُمْ ۖ وَكَثِيرٌۭ مِّنْهُمْ فَٰسِقُونَ

Then, in their wake, We followed them up with (others of) Our messengers: We sent after them Jesus the son of Mary, and bestowed on him the Gospel; and We ordained in the hearts of those who followed him Compassion and Mercy. But the Monasticism which they invented for themselves, We did not prescribe for them: (We commanded) only the seeking for the Good Pleasure of Allah; but that they did not foster as they should have done. Yet We bestowed, on those among them who believed, their (due) reward, but many of them are rebellious transgressors.