Belief in Angels is required

Moreh Nevuchim (3:45). Naturally the fundamental belief in prophecy precedes the belief in the Law, for without the belief in prophecy there can be no belief in the Law. But a prophet only receives divine inspiration through the agency of an angel. Comp. "The angel of the Lord called" (Gen. 22:15); "The angel of the Lord said unto her" (ibid. 16:11); and other innumerable instances. Even Moses our Teacher received his first prophecy through an angel. "And an angel of the Lord appeared to him in the flame of fire" (Exod. iii.). It is therefore clear that the belief in the existence of angels precedes the belief in prophecy, and the latter precedes the belief in the Law. The Sabeans, in their ignorance of the existence of God, believed that the spheres with their stars were beings without beginning and without end, that the images and certain trees, the Asherot, derived certain powers from the spheres, that they inspired the prophets, spoke to them in visions, and told them what was good and what bad. I have explained their theory when speaking of the prophets of the Ashera. But when the wise men discovered and proved that there was a Being, neither itself corporeal nor residing as a force in a corporeal body, viz., the true, one God, and that there existed besides other purely incorporeal beings which God endowed with His goodness and His light, namely, the angels, and that these beings are not included in the sphere and its stars, it became evident that it was these angels and not the images or Asherot that charged the prophets. From the preceding remarks it is clear that the belief in the existence of angels is connected with the belief in the Existence of God; and the belief in God and angels leads to the belief in Prophecy and in the truth of the Law. In order to firmly establish this creed, God commanded [the Israelites] to make over the ark the form of two angels. The belief in the existence of angels is thus inculcated into the minds of the people, and this belief is in importance next to the belief in God's Existence; it leads us to believe in Prophecy and in the Law, and opposes idolatry. If there had only been one figure of a cherub, the people would have been misled and would have mistaken it for God's image which was to be worshipped, in the fashion of the heathen; or they might have assumed that the angel [represented by the figure] was also a deity, and would thus have adopted a Dualism. By making two cherubim and distinctly declaring "the Lord is our God, the Lord is One," Moses clearly proclaimed the theory of the existence of a number of angels; he left no room for the error of considering those figures as deities, since [he declared that) God is one, and that He is the Creator of the angels, who are more than one.