10:15-22 Did not the joining in the Lord's supper show a profession of faith in Christ crucified, and of adoring gratitude to him for his salvation ? Christians, by this ordinance, and the faith therein professed, were united as the grains of wheat in one loaf of bread, or as the members in the human body, seeing they were all united to Christ, and had fellowship with him and one another. This is confirmed from the Jewish worship and customs in sacrifice. The apostle applies this to feasting with idolaters. Eating food as part of a heathen sacrifice, was worshipping the idol to whom it was made, and having fellowship or communion with it; just as he who eats the Lord's supper, is accounted to partake in the Christian sacrifice, or as they who ate the Jewish sacrifices partook of what was offered on their altar. It was denying Christianity; for communion with Christ, and communion with devils, could never be had at once. If Christians venture into places, and join in sacrifices to the lust of the flesh, the lust of the eye, and the pride of life, they will provoke God.
19, 20. What say I then?—The inference might be drawn from the analogies of the Lord's Supper and Jewish sacrifices, that an idol is really what the heathen thought it to be, a god, and that in eating idol-meats they had fellowship with the god. This verse guards against such an inference: "What would I say then? that a thing sacrificed to an idol is any real thing (in the sense that the heathen regard it), or that an idol is any real thing?" (The oldest manuscripts read the words in this order. Supply "Nay") "But [I say] that the things which the Gentiles sacrifice, they sacrifice to devils (demons)." Paul here introduces a new fact. It is true that, as I said, an idol has no reality in the sense that the heathen regard it, but it has a reality in another sense; heathendom being under Satan's dominion as "prince of this world," he and his demons are in fact the powers worshipped by the heathen, whether they are or are not conscious of it (De 32:17; Le 17:7; 2Ch 11:15; Ps 106:37; Re 9:20). "Devil" is in the Greek restricted to Satan; "demons" is the term applied to his subordinate evil spirits. Fear, rather than love, is the motive of heathen worship (compare the English word "panic," from Pan, whose human form with horns and cloven hoofs gave rise to the vulgar representations of Satan which prevail now); just as fear is the spirit of Satan and his demons (Jas 2:19).