What was Israel's role as a kingdom of priests if they already had their own priesthood?
Israel's role as a kingdom of priests was not to mediate between themselves and God, since they already had their own priesthood. Rather, the nation was to function as a corporate go-between, representing God to the Gentiles and leading them to a knowledge of Israel's God. That prospect was God preparing them as a holy nation.
Les explains that a priest is a go-between. Since Israel already had its own priesthood, the nation’s calling as a kingdom of priests was not to be a go-between between themselves and God, but between the Gentiles and God. God was beginning to deal with Israel as a nation, and all through the Old Testament He was preparing them for this national priesthood, where every Jew would be in a position to lead Gentiles to a knowledge of their God. At Acts chapter 2, on the day of Pentecost, Peter addressed a huge crowd of Jews gathered from all over the Roman Empire, continuing the frame of reference that Christ came to Israel to fulfill the Old Testament promises and covenants, making a claim on the nation even after His crucifixion and resurrection.
And ye shall be unto me a kingdom of priests, and an holy nation. These are the words which thou shalt speak unto the children of Israel.
More Questions
What kingdom is meant by Israel being a kingdom of priests?
The kingdom God promised Israel as "a kingdom of priests" is the kingdom that is coming on earth over which Christ will one day rule, not merely the nation of Israel.
Who was Israel supposed to be a priestly go-between for — themselves or the Gentiles?
Israel's national priesthood was not meant to be a go-between between the Israelites and God, since they already had their own priesthood, but between the Gentiles and God.