Howbeit then, when ye know not God
Whilst in Gentilism, and in a state of unregeneracy, they had no true knowledge of God; though they might know by the light of nature, and works of creation, that there was a God, yet they did not know who he was, but called either mortal men, or some one or other of the creatures, or stocks, and stones, and images of men's device, by this name; they knew not the God of Israel; they did not know God in Christ, and are therefore said to be without him; and a common description of them it is, that they knew not God: and whilst this was their case, what follows was true of them,
ye did service unto them which by nature are no gods;
only by name, and in the opinion of men, but have no divinity in them, are only called gods, mere nominal, fictitious deities, who have nothing of the nature and essence of God in them; for there is but one God by nature and essence, the Father, Son, and Spirit; all others have only the name and appearance, but not the truth of deity; and these the Gentiles in their times of ignorance did "service" to, which is what the Jews call (hrz hdwbe) , "strange service"; that is, idolatry, concerning which there is a whole treatise in the Talmud, and which bears that name F15. This service lay in paying homage to them, worshipping of them, and performing various rites and ceremonies in a way of adoration, and which they reckoned religious service; and which, comparatively speaking, whilst in this state of blindness, was excusable in them; though it is a wonderful instance of grace that such idolaters should be the sons of God.
F15 Aveda Zara.