“It is an error, however, to conclude from this doctrine that because all are now ‘priests’ in the New Testament Church and have equal access to God through Christ, all may rightly exercise any role involved in the life and worship of the Church. To plead the ‘priesthood of all believers’ in this way is a little different from Korah's contention that ‘all the congregation is holy’ and should therefore have an equal right to the functions of Moses and Aaron.
The truth of the matter is that God continues to make distinctions in office and function, even in the New Testament Church, and with His commanded distinctions we ought to be content. ‘Now you are the body of Christ and members individually. And God has appointed these in the church: first apostles, second prophets, third teachers, after that miracles, then gifts of healings, helps, administrations, variety of tongues. Are all apostles? Are all prophets? Are all teachers? Are all workers of miracles? Do all have gifts of healings? Do all speak with tongues? Do all interpret? (1 Cor. 12:27-30).
The order of office and function that God has established within His Church is designed to reflect His provision in Christ and His people's dependence upon His word through Christ for salvation. To deny God's appointed offices, or the distinction of function that He has prescribed, is to exalt man's judgment over God’s and put individuals- apart from His calling, gifting and appointing them as His representatives- in the place of God.
It is also an error to conclude from the priesthood of all believers that every Christian has the right to ‘add something’ to the service of worship through the exercise of his or her particular gifts. Even the priests of the Old Covenant did not have the prerogative to invent rites and ordinances to be added to God's commands for worship. Why then would it be assumed that Christ’s fulfillment of the symbolism of the priesthood opens the way for individuals to set aside His commanded ordinances and determine for themselves how God is to be worshipped?” (Douglas Comin, Worship from Genesis to Revelation, 2007, p. 42-43)