Isn't it funny how people forget that at the time Christianity, and indeed Judaism, were founded, Yahweh was just one god among many?

Yahweh did not tell Moses that there were no other gods, but that "You shall have no other gods before Me!"

Genesis tells us that 'the gods' (Elohim, plural) created the world. Throughout the Old Testament there are ambiguities around the concept of monotheism. Historically, Jews were considered odd not for claiming other gods did not exist, but for refusing to honour any but their particular one. The specific god with whom their ancestors had made a covenant.

So this Abrahamic god, then, denied his heaven and his blessing to those who did not follow his laws and commandments. But it is only in the later stages of the New Testament, when Christianity was becoming more powerful, that we find the threat of damnation being levelled at the followers of other gods.