But now, all Christians, even the least of them, are part of “a royal priesthood.” Even at Peter’s time, many Christians were Gentiles according to the flesh. As such, they were not allowed to come into the temple proper: they could come only as far as the Court of the Gentiles. Now, in Jesus Christ, Gentile Christians have what an ordinary Jew could never hope to be—not even all the kings of Israel, including David! How can this come about?
You see, Israel was a holy nation in the sense that it was set apart from the world to God through the Sinaic Covenant. But it never became a holy nation in the sense that it was a kingdom of priests. It could never be as long as it remained under the Sinaic Covenant. For it was the Sinaic Covenant, which set the priests aside as a separate class. Unless one was born into the line of Aaron, he could never be a priest. In order for Israel to be a kingdom of priests, it had to be under a new, different covenant—the kind of covenant which made all of God’s people priests!
This is precisely what Jesus has done through the new covenant. Because Jesus offered Himself as the once-for-all sacrifice for all our sins, the animal sacrifices became unnecessary. This rendered the temple and the priestly office unnecessary as well. This new situation called for a radically different kind of worship and reorganization of God’s people—a worship without animal sacrifices, without the priests to offer up the sacrifices, and without the temple where the sacrifices were made.