The word archiereus , “chief priests,” is used twenty-five times in Matthew.  They are always cast in the role of villains.  They first appear as advisors to Herod (2:4), then as the ones who will cause Jesus to suffer many things (16:21).  They appear in person again only in 21:15, when Jesus enters Jerusalem and does wonders in the temple, and from that point they dominate the action.

The 25 uses of the word point to the 25 chief priests in the post-Davidic priesthood - 24 priests, each head of a clan of priests, and the high priest.  In Matthew, the chief priests are like the 25 idolatrous priests in Ezekiel 8:11 and 11:1.  They are the demonic, earthly counterpart to the heavenly assembly of priests in Revelation 4 - twenty-four “angels” who are awaiting the appearance of the Chief Priest, the Lamb.