Angelology and demonology of Israel.
The doctrine of monotheism was formally expressed in the period immediately before and during the Exile, in Deuteronomy" and Isaiah; and at the same time we find angels prominent in Ezekiel who, as a prophet of the Exile, may have been influenced by the hierarchy of supernatural beings in the Babylonian religion, and perhaps even by the angelology of Zoroastrianism."
Later Jewish and Christian speculation followed on the lines of the angelology of the earlier apocalypses; and angels play an important part in Gnostic systems and in the Jewish Midrashim and the Kabbala.
The views on angelology and demonology, on purgatory, the Eucharistic Sacrifice, and the efficacy of relics).
Most noticeable among these doctrines is the complete system of angelology consistently followed out in the Book of Daniel, according to which the management of human affairs is entrusted to a regular hierarchy of commanding angels, two of whom, Gabriel and Michael, are even mentioned by name.
It could certainly not have come from the Babylonians, however, whose system of attendant spirits was far from being so complete as that which is set forth in the Book of Daniel, but rather from Persian sources where a more complicated angelology had been developed.