Axtec religions had ethical standards but, otherwise, their ethics were largely nonexistent, unless others can say better. They had no rules against brutality and violence.

Stanley Wilkins, we truly do not know much about the Aztec religion. Virtually everything we know about it was written by outsiders. An outsider writing about Christianity, Judaism or Islam might conclude the same thing about these religions, as while mouthing good intentions, they have often in their history openly supported violence. Hinduism and Buddhism also have less than ideal practices which do not always meet the professed standards for behavior. These peace-loving religions are also the source of various forms of martial arts which may be used aggressively. In modern America even, Trump's vision loudly proclaims its Christian roots, while ignoring much of what Christianity teaches.

Thus, the answer, to my mind, at various times, virtually every culture has outwardly expressed compassionate religious values while failing to actually practice what it proclaims it believes.