In Exodus God prepares to show Himself to the entire nation of Israel (Ex. 19.11) and invites the entire community up onto the Holy Mountain (Ex. 19.13) to encounter Him.  Upon witnessing the smoke and lightning and hearing the trumpet and thunder on the Holy Mountain the people instead distance themselves from the mountain and select Moses as their representative (Ex. 20.18-21).  God accommodates their lack of faith by instituting a Priestly system that concentrates the ministry of the Priest to a small group of people (Ex. 21-30).

In Numbers God takes the Spirit that is upon Moses and places the same Holy Spirit upon 70 other men who can now prophesy just as Moses did (Num. 11.17, 25). Joshua, apparently concerned for Moses' job security, asks Moses to restrain the group of 70 men from prophesying (Num. 11.28). Moses responds by saying "Are you jealous for my sake? I wish that all of the Lord's people were prophets and that His Spirit would be upon them!" (Num. 11.29).  Nevertheless this group never prophesies again (Num. 11.25) and the ministry of the Prophet is concentrated to a small group of consecrated and marginalized people.

In 1 Samuel the people live directly under God's Kingship but grow weary of not having a human King to lead them. They want someone to fight their battles for them (1 Sam. 8.20).  Despite being warned that a human king will send their children into war and servitude, take their land and tax their crops the people still demand a human king (1 Sam. 8.10-19).  Though God sees this as a direct rejection of His leadership (1 Sam. 8.7), He again accommodates the people's lack of faith and provides them with King Saul. They people forfeit some of their autonomy for an imperfect monarchy and one man makes decisions for an entire nation.

The entire Old Testament bears examples of God's people refusing to consecrate themselves and carry out their responsibilities, instead appointing a small group of people to do the entire communities job. In some ways, this attitude still fuels the modern day clergy/laity dichotomy.

The purpose of clergy (if we can even use that word) is to equip the saints for ministry, not replace the saints in ministry (Eph. 4.12).

But in the New Testament we move from ministerial concentration to ministerial distribution. 1 Peter 2.9 declares all believers to be a royal priest. Acts 2.17-18 implies that God agrees with Moses and Paul (1 Cor. 14.1) that prophesying would be a responsibility that is not concentrated to a small group of people, but a responsibility that is distributed to the entire church. Not everyone who evanglizes is an evangelist, but all can/should evangelize. Not everyone who prophesies is a prophet, but all can/should prophesy.

And finally, in the New Testament the throne is returned directly to God as Jesus is declared the King and we receive autonomy under subjection to Him and no other King.