Prohibition of compromising faith for worldly gain

وَلَا تَشْتَرُوا۟ بِعَهْدِ ٱللَّهِ ثَمَنًا قَلِيلًا ۚ إِنَّمَا عِندَ ٱللَّهِ هُوَ خَيْرٌ لَّكُمْ إِن كُنتُمْ تَعْلَمُونَ

And do not exchange the covenant of Allāh for a small price. Indeed, what is with Allāh is best for you, if only you could know.