Behold Israel - Look at the Jews. The design here is to illustrate the sentiment which he was establishing, by a reference to the fact that among the Jews those who partook of the same sacrifices were regarded as being one people, and as worshipping one God. So, if they partook of the sacrifices offered to idols, they would be regarded also as being fellow-worshippers of idols with them.

After the flesh - See Romans 4:1. The phrase "after the flesh" is designed to denote the Jews who were not converted to Christianity; the natural descendants of Israel, or Jacob.

Are not they which eat of the sacrifices - A portion of the sacrifices offered to God was eaten by the offerer, and another portion by the priests. Some portions of the animal, as the fat, were burnt; and the remainder, unless it was a holocaust, or whole burnt-offering, was then the property of the priests who had officiated, or of the persons who had brought it; Exodus 29:13, Exodus 29:22; Lev, Leviticus 3:4, Leviticus 3:10, Leviticus 3:15; Leviticus 4:9; Leviticus 7:3-4; Leviticus 8:26. The right shoulder and the breast was the part which was assigned to the priests; the remainder belonged to the offerer.

Partakers of the altar - Worshippers of the same God. They are united in their worship, and are so regarded. And in like manner, if you partake of the sacrifices offered to idols, and join with their worshippers in their temples, you will be justly regarded as "united" with them in their worship, and partaking with them in their abominations.

Behold Israel after the flesh - The Jews not yet converted to Christianity: the latter being Israel after the Spirit. As the design of the apostle was to withdraw his converts at Corinth from all temptations to idolatry, he produces two examples to show the propriety of his endeavors.

1. All who join together in celebrating the Lord's Supper, and are partakers of that one bread, give proof by this that they are Christians, and have fellowship with Christ.

2. All the Israelites who offer sacrifice, and partake of those sacrifices, give proof thereby that they are Jews, and are in fellowship with the object of their worship: so they who join in idol festivals, and eat things which have been offered to idols, give proof that they are in communion with those idolaters, and that they have fellowship with the demons they worship.

Behold Israel after the flesh,.... So the apostle calls them, to distinguish them from the Israel of God, the spiritual Israel, whether Jews or Gentiles; who are born again, believe in the true Messiah, worship God in a spiritual manner, rejoice in Christ Jesus, and have no confidence in fleshly things; but these were the descendants of Jacob or Israel by carnal generation, were carnal men, in the flesh, in a state of unregeneracy, and were employed in a carnal worship, in the observance of carnal commandments and ordinances; these the apostle directs to, to see, consider, and take notice of what they were doing; from whence some instruction might be taken, for the further clearing of the present point:

are not they which eat of the sacrifices partakers of the altar? yes, they are. The priests and Levites who waited at the altar, and ministered about holy things there, who brought the sacrifices and laid them upon the altar of the burnt offerings, where the altar consumed and devoured one part by fire, and that which was left they ate among themselves; and so as they had communion with one another in eating, they partook of the altar, of the things, or sacrifices of the altar, and showed themselves to be of the Jewish religion, and professed and declared that they worshipped the God of Israel, and would be thought to have communion with him in so doing; in like manner, such who eat of things sacrificed to idols, declared themselves to be idolaters, to be of the Pagan religion, to be worshippers of idols, and to have fellowship with them.

Showing that partaking of the idol-feasts is idolatry, by the analogy of the Israelite who, by partaking of the sacrifices puts himself in communion with Jehovah's altar.

Partakers of the altar (κοινωνοὶ τοῦ θυσιαστηρίου)

An awkward phrase. Rev., better, bringing out the force of κοινωνοὶ communers: have not they - communion with the altar? The Israelite who partook of the sacrifices (Leviticus 8:31) united himself with the altar of God. Paul says with the altar rather than with God, in order to emphasize the communion through the specific act of worship or sacrifice; since, in a larger sense, Israel after the flesh, Israel regarded as a nation, was, in virtue of that fact, in fellowship with God, apart from his partaking of the sacrifices. Possibly, also, to suggest the external character of the Jewish worship in contrast with the spiritual worship of Christians. Philo calls the Jewish priest κοινωνὸς τοῦ βώμου partaker of the altar.

Behold Israel after the {p} flesh: are not they which eat of the sacrifices {q} partakers of the altar?

(p) That is, those who yet observe their ceremonies.

(q) Are consenting and guilty, both of that worship and sacrifice.

10:18 Behold Israel after the flesh. The natural Israel, in contrast with the spiritual Israel, the church.

Are not they which eat of the sacrifices partakers of the altar? A part of the sacrifice was eaten by the offerers and their friends, and as a part was burnt on the altar, as an offering to God, they were supposed to be partakers with God in the feast. So, too, those who partook of an idol feast, would be worshipers of the idol.

10:18 Consider Israel after the flesh - Christians are the spiritual Israel of God. Are not they who eat of the sacrifices partakers of the altar - Is not this an act of communion with that God to whom they are offered? And is not the case the same with those who eat of the sacrifices which have been offered to idols?

18. Israel after the flesh-the literal, as distinguished from the spiritual, Israel (Ro 2:29; 4:1; 9:3; Ga 4:29).

partakers of the altar-and so of God, whose is the altar; they have fellowship in God and His worship, of which the altar is the symbol.

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.