The early Hebrews were similar in every respect tot their neighbors. They too believed in holy wells, holy shrines, holy stones, and other fetishes. They had no concept of a supreme god as they had no concept of the universe. Yahweh was their tribal all father who later became their war god. He was more easily roused by anger like most other early deities.
For the Hebrews the world was full of spirits controlling and directing human affairs. When tribes developed, each hit upon a deity as its tribal god. Yahweh was one of them. There are disputes as to whether, it was Moses who introduced the name Yahweh. . Solomon built a temple in Jerusalem for this god but that did not prevent him from worshipping other gods (1 Kings, 11:36)
They had a highly elaborate cult of the dead. The old testament is full references to it. The corpse was unclean and hence a taboo. The graves of the patriarchs were sacred shrines. Ancestral worship was very much prevalent and strong.
In the earliest times there was no priest and they dealt with the god themselves. But when magical and ritual practices got elaborated professional priests appeared.
It was not until the time of Jeremiah that a sort of monotheism appeared among the people. Isaiah ridiculed the idea that there can be more than one god. Yahweh slowly became the undisputed god. With the prophets, this developed into monotheism.
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