Heb 8:4

“And in another way; Having said that He is on high, he affirms and proves that He is a Priest from every consideration, from Melchisedec, from the oath, from offering sacrifice. From this he also frames another and necessary syllogism. "For if" (he says) "He had been on earth, He would not be a Priest, seeing that there are priests who offer the gifts according to the Law." If then He is a Priest (as He really is), we must seek some other place for Him. "For if He were" indeed "on earth, He should not be a priest." For how could He be? He offered no sacrifice, He ministered not in the Priest's office. And with good reason, for there were the priests. Moreover he shows, that it was impossible that He should be a priest upon earth. For how could He be? There was no rising up against the appointed Priests, he means.”

“He mentioned this by way of defense to stress that he was not criticizing the law but regarding it also as venerable for containing the type of the heavenly things. This was the reason he said it was pointless to refer to him as a priest while living on earth, there being priests according to the law discharging the worship prescribed by the law. So if the priesthood according to the law also came to an end, and the high priest according to the order of Melchizedek offered sacrifice and made further sacrifices unnecessary, why do the priests of the New Covenant perform the sacramental liturgy? It is clear to those versed in divine things, however, that it is not another sacrifice we offer; rather, we perform the commemoration of the one, saving sacrifice. The Lord himself, remember, required this of us, "Do this in memory of me," so that we should recall with insight the type of the sufferings undergone for us, kindle love for the benefactor and look forward to the enjoyment of the good things to come.”

“He further confirms that although He does not have His tabernacle on earth but in heaven, there is nevertheless no obstacle to His being a priest. And notice the wisdom. On the very basis by which someone might especially argue that He is not a priest — I mean, of course, that He does not have a place on earth where He served as priest — on this very basis he most strongly affirms that He is a Priest, and says that He is a Priest precisely because He did not have a place on earth. "If He were remaining on earth, He would not even be a priest." For there were other priests on earth, and this circumstance would seem to be a refutation. But now, having heaven as His place, and having brought up there His own body, He intercedes for us before the Father. Hence, since He is in heaven, He is therefore preeminently a Priest.”

“385. – Then (v. 4) he shows that Christ is not a minister of the sacrifices of the Law. In regard to this he does three things: first, he introduces a consequence; secondly, he gives the reason (v. 4b); thirdly, he proves it by an authority (v. 4c). 386. – The consequence is this: If he were on earth (this is the antecedent), he would not be a priest at all (this is the consequent). Hence, the consequence is one conditional proposition. And it is read in a number of ways: first, according to a Gloss: for 'if that which is offered were on earth, he would not be a priest.' This can be understood in two ways: in one way so that the sense would be: If that which is offered were something earthly, Christ would not be a priest. As if to say: There would be no need for a priesthood, because there would be many to offer such things. But was not the flesh of Christ earthly? I answer that materially speaking it was earthly: 'The earth is given into the hand of the wicked' (Jb. 9:24). But it is said not to be earthly by reason of the union: 'He that comes from heaven is above all' (Jn. 3:31), i.e., the Son of God, Who united it to Himself. Also, by reason of the active power of the Holy Spirit, Who formed it; and by reason of the fruit, because His oblation is not ordained to obtaining something earthly: 'You are of this world; I am not of this world' (Jn. 8:23). This is the first and better explanation. The second is this: 'Even if,' i.e., although that which is offered 'is on earth,' because it is necessary that something be offered, 'He would not be a priest,' but someone worthy, because no one could be found worthy to offer it. 387. – There are three readings in which the one offering is understood: first, in general, so that the sense is this: If there were another earthly priest, who could offer heavenly things, Christ would not be a priest. Another is of Christ specifically: If Christ were an earthly priest, the right of the priesthood would not belong to Him, since there are priests who offer gifts according to the law. Still another is the following: If Christ were still on earth, in the sense that He had not yet ascended, He would not be a priest, because He would not have completed His priesthood.”

“If then he were on earth, he would not be a priest. He speaks of a priest according to the custom of the Jews, where none were priests but of the tribe of Levi, and Jesus Christ was of the tribe of Juda: and if the law of Moses was to continue, there would not be wanting priests to offer sacrifices according to their worship, though such priests were only employed about things that were types[2] and shadows of heavenly things in the new law after Christ’s coming, and of the sacrifice by which he offered himself on the cross. And this God doubtless revealed to Moses, when he said to him: take heed “thou make all things according to the pattern which was shewn thee on the mount.” (Witham) — Earth, &c. That is, if he were not of a higher condition than the Levitical order of earthly priests, and had not another kind of sacrifice to offer, he should be excluded by them from the priesthood, and its functions, which by the law were appropriated to their tribe. (Challoner)”

“Implying that Christ's priestly office is exercised in heaven, not in earth; in the power of His resurrection life, not of His earthly life. For--The oldest manuscripts read, "accordingly then." if, &c.--"if He were on earth, He would not even (so the Greek) be a priest" (compare Heb 7:13-14); therefore, certainly, He could not exercise the high priestly function in the earthly Holy of Holies. seeing that, &c.--"since there are" already, and exist now (the temple service not yet being set aside, as it was on the destruction of Jerusalem), "those (the oldest manuscripts omit 'priests') who offer the (appointed) gifts according to (the) law." Therefore, His sacerdotal "ministry" must be "in the heavens," not on earth (Heb 8:1). "If His priesthood terminated on the earth, He would not even be a priest at all" [BENGEL]. I conceive that the denial here of Christ's priesthood on earth does not extend to the sacrifice on the cross which He offered as a priest on earth; but applies only to the crowning work of His priesthood, the bringing of the blood into the Holy of Holies, which He could not have done in the earthly Holy of Holies, as not being an Aaronic priest. The place (the heavenly Holy of Holies) was as essential to the atonement being made as the oblation (the blood). The body was burnt without the gate; but the sanctification was effected by the presentation of the blood within the sanctuary by the high priest. If on earth, He would not be a priest in the sense of the law of Moses ("according to the law" is emphatic).”

“"For if he were on earth." This was the case, if he had not died, nor had he been taken up after rising. "he would not be a priest at all." For there would be others, even a rebellion would be present. But now he has died, so that he may offer the sacrifice. Rising from the dead, he was taken up, so that he might have a place in heaven, where he must serve as a priest. To serve as a priest means to intercede for us. All these humble words were said, both because of humanity and because of the childishness of those who hear.”