If therefore perfection were by the Levitical priesthood, (for under it the people received the law,) what further need was there that another priest should rise after the order of Melchizedek, and not be called after the order of Aaron?
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If therefore (he says) perfection were by the Levitical priesthood. Having spoken concerning Melchisedec, and shown how much superior he was to Abraham, and having set forth the great difference between them, he begins from this point forward to prove the wide difference as to the covenant itself, and how the one is imperfect and the other perfect. However he does not even yet enter on the matters themselves, but first contends on the ground of the priesthood, and the tabernacle. For these things would be more easily received by the unbelieving, when the proof was derived from things already allowed, and believed.
He had shown that Melchisedec was greatly superior both to Levi and to Abraham, being to them in the rank of the priests. Again he argues from a different point. What then is this? Why (he says) did he not say, after the order of Aaron? And observe, I pray you, the great superiority [of his argument]. For from the very circumstance which naturally excluded His priesthood, viz. that He was not after the order of Aaron, from that he establishes Him, and excludes the others. For this is the very thing that I say (he declares); why has He not been made after the order of Aaron?
And the [saying] what further need has much emphasis. For if Christ had been after the order of Melchisedec according to the flesh, and then afterwards the law had been introduced, and all that pertained to Aaron, one might reasonably say that the latter as being more perfect, annulled the former, seeing that it had come in after it. But if Christ comes later, and takes a different type, as that of His priesthood, it is evident that it is because those were imperfect. For (he would say) let us suppose for argument's sake, that all has been fulfilled, and that there is nothing imperfect in the priesthood. What need was there in that case that He should be called after the order of Melchisedec and not after the order of Aaron? Why did He set aside Aaron, and introduce a different priesthood, that of Melchisedec? If then perfection, that is the perfection of the things themselves, of the doctrines, of life, had been by the Levitical priesthood.
And observe how he goes forward on his path. He had said that [He was] after the order of Melchisedec, implying that the [priesthood] after the order of Melchisedec is superior: for [he was] far superior. Afterwards he shows this from the time also, in that He was after Aaron; evidently as being better.