We have an altar, etc. This is a beautiful adaptation of an old rite under the Law, to the present state of the Church. There was a kind of sacrifice appointed, mentioned in the sixteenth chapter of Leviticus, no part of which returned to the priests and Levites. This, as he now shows by a suitable allusion, was accomplished in Christ; for he was sacrificed on this condition, that they who serve the tabernacle should not feed on him. But by the ministers of the tabernacle he means all those who performed the ceremonies. Then that we may partake of Christ, he intimates that we must renounce the tabernacle; for as the word altar includes sacrificing and the victim; so tabernacle, all the external types connected with it. Then the meaning is, "No wonder if the rites of the Law have now ceased, for this is what was typified by the sacrifice which the Levites brought without the camp to be there burnt; for as the ministers of the tabernacle did eat nothing of it, so if we serve the tabernacle, that is, retain its ceremonies, we shall not be partakers of that sacrifice which Christ once offered, nor of the expiation which he once made by his own blood; for his own blood he brought into the heavenly sanctuary that he might atone for the sin of the world." [1]

Footnotes

1 - The verb hagiazo means here expiation, as in chapter 2:11, 10:10, and other places in this Epistle; and so it is taken by Calvin and the rendering of Stuart is "that he might make expiation," etc. -- Ed

We have an altar - We who are Christians. The Jews had an altar on which their sacrifices were offered which was regarded as sacred, and of the benefit of which no others might partake. The design of the apostle is to show that the same thing substantially, so far as "privilege" and "sanctifying influence" were concerned, was enjoyed by Christians. The "altar" to which he here refers is evidently the cross on which the great sacrifice was made.
Whereof they have no right to eat which serve the tabernacle - A part of the meat offered in sacrifice among the Jews became the property of the priests and Levites, and they had, by the Law, a right to this as a part of their support; see Leviticus 6:25-26; Numbers 18:9-10. But the apostle says that there is a higher and more valuable sacrifice of which they have no right to partake while they remain in the service of the "tabernacle" or temple; that is, while they remain Jews. The participation in the great Christian sacrifice appertained only to those who were the friends of the Redeemer, and however much they might value themselves on the privilege of partaking of the sacrifices offered under the Jewish Law, that of partaking of the great sacrifice made by the Son of God was much greater.
Which serve the tabernacle - notes, Hebrews 9:2-3. The Jewish priests and Levites.

We have an altar - The altar is here put for the sacrifice on the altar; the Christian altar is the Christian sacrifice, which is Christ Jesus, with all the benefits of his passion and death. To these privileges they had no right who continued to offer the Levitical sacrifices, and to trust in them for remission of sins.

(7) We have an (f) altar, whereof they have no right to eat which (g) serve the tabernacle.
(7) He refutes their error by an apt and fit comparison. They who in times past served the Tabernacle, did not eat of the sacrifices whose blood was brought for sin into the holy place by the high priest. Moreover these sacrifices represented Christ our offering. Therefore they cannot be partakers of him if they serve the tabernacle, that is, stand in the service of the law: but let us not be ashamed to follow him out of Jerusalem, from which he was cast out and suffered for in this also Christ, who is the truth, answers that type in that he suffered outside the gate.
(f) By the altar, he means the offerings.
(g) Of which they cannot be partakers, who stubbornly retain the rites of the law.

We have an altar,.... By which is meant, not the cross of Christ, on which he was crucified; nor the Lord's table, where his flesh and blood are presented to faith, as food, though not offered; but Christ himself, who is altar, sacrifice, and priest; he was typified by the altar of the burnt offering, and the sacrifice that was offered upon it; the altar was made of Shittim wood, and covered with brass, denoting the incorruptibleness, duration, and strength of Christ: the horns of it, at the four corners, were for refuge; whoever fled to it, and laid hold on them, were safe; so Christ is a refuge to his people, that come from the four corners of the earth; and who believe in him, and lay hold on him, are preserved and protected by his power and grace: the use of it was for sacrifice to be offered upon it; which being a male, without blemish, and wholly burnt with fire, was a sweet savour to God; and which was typical of Christ's human nature, offered on the altar of his divine nature; which was pure and holy, suffered the fire of divine wrath, and was for a sweet smelling savour to God: this altar was but one, and most holy, and sanctified what was put upon it; all which is true of Christ: now this altar the saints have, and have a right to eat of it; even all Christ's friends and beloved ones; all that are made priests unto God by him; all that know him, believe in him, have a spiritual discerning of him, and hunger and thirst after him:
whereof they have no right to eat that serve the tabernacle: there is something of this altar, or that was offered up upon this altar, that is to be eaten, even the flesh and blood of Christ; and to "eat" of it is to believe that Christ is come in the flesh, and is become an offering for sin, and for us that eat; it is to receive, embrace, and possess the blessings procured by it; which is done by faith, with spiritual joy and gladness, and with sincerity and singleness of heart: now those, who served the tabernacle, or adhered to the service of the ceremonial law, they had no right to eat of this altar: the allusion is to the priests' eating of the sacrifices, and to some sacrifices, of which they might not eat, Leviticus 2:10 and this is not to be understood of believers, before the coming of Christ, who did attend tabernacle service; for they ate the same spiritual meat, and drank the same spiritual drink, as believers do now; but of such, who obstinately persisted in the ceremonies of the law, when they were abolished; and so cut off themselves from all right to the substance of these shadows. See Galatians 5:2.

Christianity and Judaism are so totally distinct, that "they who serve the (Jewish) tabernacle," have no right to eat our spiritual Gospel meat, namely, the Jewish priests, and those who follow their guidance in serving the ceremonial ordinance. He says, "serve the tabernacle," not "serve IN the tabernacle." Contrast with this servile worship ours.
an altar--the cross of Christ, whereon His body was offered. The Lord's table represents this altar, the cross; as the bread and wine represent the sacrifice offered on it. Our meat, which we by faith spiritually eat, is the flesh of Christ, in contrast to the typical ceremonial meats. The two cannot be combined (Galatians 5:2). That not a literal eating of the sacrifice of Christ is meant in the Lord's Supper, but a spiritual is meant, appears from comparing Hebrews 13:9 with Hebrews 13:10, "with GRACE, NOT with MEATS."

On the former part of this verse, Hebrews 13:15-16 depend; on the latter, Hebrews 13:11-14. We have an altar - The cross of Christ. Whereof they have no right to eat - To partake of the benefits which we receive therefrom. Who serve the tabernacle - Who adhere to the Mosaic law.