This kind of transmission can be due to lack of other means, such as in illiterate or criminal societies, or can be expressly required by the same law.
It has been pointed out that "The laws governing such matters as hospitality, the rights of the heads of households, marriage, blood-feuds and payment of damages find precise echoes in Vedic India and ancient Greece and Rome".
[8] According to some historical sources, the government of the Roman and Byzantine empire had to recognize autonomous customary laws to the various local communities for their self-administration.
[9][8] This helped the Albanian mountain tribes to preserve their way of life, identity, and neutrality in the face of external centralizing administration.
[4] Rabbinic Judaism maintains that the books of the Tanakh were transmitted in parallel with an oral tradition, as relayed by God to Moses and from him handed on to the scholarly and other religious leaders of each generation.