What is the name of a law that criminalizes an act that was innocent when it was committed?

the social contract theory

arianism, proposed by arius in the third century ce, proposed that jesus christ could not be god because god himself is unique and immutable. this would mean that jesus christ was created by god and therefore lesser. this was considered heretical and banned from orthodoxy, but caught on in germanic cultures. developed approximately around 500 bce by gautama buddha in northeastern india, buddhism first spread to central asia and southeast asia after a few centuries.   shortly thereafter it spread into china, korea, and japan. although initially rome's government persecuted early christian communities, the roman emperor constantine tolerated christians and even converted to christianity himself; christianity became the official state religion. the athenian empire and the nabataeans existed before christianity. the hunnic empire, a great enemy to rome, was never christian. the mongol empire had a christian population that was tolerated but was never officially christian.