21. And I will even take some of them for priests and Levites. The Prophet heightens the description of that which he had already declared about the extraordinary grace of God. He had made known that the Church of God should be collected out of all nations, so that, in spite of every difficulty and obstruction, even distant nations should draw near to them. But now he proceeds further, and instructs them that the Gentiles shall not only be adopted by God, but shall also be elevated by him to the highest honor. Already it was a great honor, that unclean and polluted nations were reckoned to be a holy people; but now here is something far more wonderful, that they are elevated to the highest pinnacle of rank.
Hence we see that the priesthood under Christ is very different from what it was under the Law; for under the Law one tribe exclusively was admitted to the priesthood, and the Gentiles, as unclean, were so far from having it in their power to discharge that priesthood, that they were even forbidden to enter into the temple; but now all are admitted without distinction. Some expound this passage in a general manner, that the Gentiles shall be priests; that is, shall offer themselves to God, as Scripture frequently denominates all believers “a royal priesthood.” (1 Peter 2:9; Revelation 1:6.) But he appears to describe in an especial manner ministers and teachers whom the Lord also chose from among the Gentiles, and appointed to execute this distinguished office; that is, to preach the Gospel; such as Luke, Timothy, and others of the same class, who offered spiritual sacrifices to God by the Gospel.