Thus He, glorified be He, explains that their forgetting a portion of what they had been reminded of caused enmity and hatred to arise among them. When a person follows all the prescribed practices of the sunnah, observing one prescribed form at one time and another at another time, the sunnah is preserved in both knowledge and practice, and the harm feared from abandoning this is averted. The essential point here is that, although confining oneself to one form is permissible, preserving the other form is part of the religion, so that its permissibility and prescribed status remain known. Practising it on occasion preserves the revealed law, whereas abandoning it may cause it to be lost and forgotten.

Seventh:

Allah commands justice and good conduct. Justice means treating like cases alike. He has forbidden injustice for Himself and made it forbidden among His servants. Among the greatest forms of justice is justice in religious matters. Although justice in worldly matters involving lives and property—such as legal retribution and inheritance—is obligatory, and failing to uphold it is injustice, justice in religious matters is still greater. This means dealing justly with the prescribed practices of the religion and with its adherents.

If the Lawgiver has accorded equal standing to two deeds or two people who perform them, then favoring one over the other is a grave injustice. If He has given one precedence over the other, treating them as equal is likewise unjust. Favoring one over another, or treating them as equal, on the basis of conjecture and personal desires is characteristic of the religion of the disbelievers. For the adherents of every religion and creed favor their own religion, whether through conjecture or desire, whether in belief or conduct. This is what leads them to hold fast to it and disparage other religions.