Deuteronomy 4:15-20 -

As the people had seen no form or figure when God spake to them, so they were to beware for their very lives (cf. Deuteronomy 4:9 ) of acting corruptly by making any kind of image, whether of man or of beast, for the purpose of worshipping God as represented by it; they were also to beware of being so attracted by the splendor of the heavenly bodies as to be forcibly seduced to worship them and offer them religious service. They were not in this respect to imitate the heathen; for God, who had delivered them out of the furnace of Egyptian bondage, had taken them for himself to be his special possession; and therefore they were to take heed not to forget the covenant of Jehovah their God, nor to offend him by making any image or representation of him as the object of worship. Among the heathen, and especially in Egypt, images were the very pillar and support of religion; but in Israel, as God had revealed himself to them without form, it was as a spirit he was to be worshipped, and not under any outward representation.