A friend asked me if priesthood was given in the Early Christian Church to the membership who were called, ordained, and set apart as Elders (Presbyters) and Deacons (Diaconos), then how could there be an Apostasy of Christ's Church. Although the Apostles, and Bishops were martyred or removed, couldn't the Elders and Deacons choose new Bishops and leaders?
The key to answering this question is to understand the keys. In Matt 16 Jesus says he will give Peter the keys of the kingdom and also the sealing power that whatsoever he binds on Earth will be bound in heaven. The Sealing power with the keys are the preisthood of God to speak and act in the name of God on the Earth. However, the keys of the priesthood are something distinct from the sealing (binding and losing) power itself. In Matt 18, Jesus gives the rest of the disciples the Sealing power only but no keys. What is the difference?
The sealing power or Priesthood is the authority to administer the rites and ordinances and blessings of the gospel of Christ. But, only the keys have the authority to authorize them to be done. What do I mean?
I am an ordained Presbyter or Elder in the LDS church. But I have not a single key. While I do not need keys or authorization to bless, anoint, and visit the sick, fatherless, and widow; and while I can baptize, confer the gift of the holy ghost, and ordain other Elders and Deacons, and administer the Lords Supper, and officiate in the temple to administer the everlasting temple covenant (Ez 37:26-29); I can't decide myself and authorize the baptism of someone else, or the ordaining of another Elder or decide to start my own congregation and do my own sacrament service, or build my own temple and officiate my own temple ordinances. I don't have keys. (the bestowal of keys is specifically stated or excluded when someone is ordained in the priesthood).
How does this work in the LDS church? While all worthy male members are ordained to the priesthood; and either made Elders and ordained to the Melchizedek Priesthood or are ordained in the Aaronic Priesthood and are Deacons; keys are not given. Only those who are Bishops or hold the office of a president are given keys. And not all Presidents are given every key. A Temple president doesn't authorize sacrament meetings and Bishops don't authorize temple ordinances. But only the Chief Apostles who is the President of the church holds all the keys at one time and the Quorum of the 12 Apostles as a whole who can authorize anything that is required to be done in Christs church.
And this is why Ignacius said clearly to the Deacons "Do not do anything in the church without the Bishop" The Bishop had the keys. This is why after the Apostles were martyred, and the Bishops were either martyred or removed, the keys were lost, and the remaining Elders and Deacons could not replace them. And according to Clement and other Early Church Fathers over and over again, Bishops were appointed from the top down by "eminent men," and not elected in from the bottom up. The Deacons and Presbyters had authority but they didn't have the keys.
Again, the Bishop as head of the congregation holds the priesthood keys to approve and authorize the rites and ordinances. The Deacons and the Presbyters had the sealing or binding authority to participate and assist the Bishop in the administration of these rites and ordinances.
Epistle to the Smyrnæans Chapter 8
See that ye all follow the bishop, even as Jesus Christ does the Father, and the presbytery as ye would the apostles; and reverence the deacons, as being the institution (Or, “command.”) of God. Let no man do anything connected with the Church without the bishop. Let that be deemed a proper Eucharist, which is [administered] either by the bishop, or by one to whom he has entrusted it. Wherever the bishop shall appear, there let the multitude [of the people] also be; even as, wherever Jesus Christ is, there is the Catholic Church. It is not lawful without the bishop either to baptize or to celebrate a love-feast; but whatsoever he shall approve of, that is also pleasing to God, so that everything that is done may be secure and valid.
Ignatius clearly says you cant have a Lord's Supper or a Baptism without the Bishop. This is because the Bishop is given Keys to approve and authorize the sanctifying rites and ordinances of the gospel. According to Clement, Bishops were to be appointed by the Apostles or other "emminent men" in the Church hierarchy. After the Apostles were martyred and the Bishops were removed or martyred, the keys were lost. Presbyters had the high priesthood and had the binding authority to officiate in the ordinaces and to annoint and bless under the direction of the Bishop who had the keys.This is why Peter was given keys and "sealing power" in Matt 16, but the disciples were only given "binding power" in Matt 18. While the High Priesthood is authority. The proper use of this authority depends on being empowered by the Holy Ghost. The Holy Ghost empowers priesthood authority through faith in Jesus Christ.Any believer with the Holy Ghost can enjoy every miricle and blessing the the greatest prophet or apostle could. But they cannot bless others without the preisthood. The purpose of priesthood is to elicite those same blessings for the benifit of others, recieve revelation for other, perform sanctifying ordinances in the name of Jesus Christ for others.
The Power of the Priesthood
Now what about the power of the priesthood? The Holy Ghost is the Power by which the authority of the Priesthood operates. Anyone who acts by the keys and authority of the priesthood must do so in the name of Jesus Christ who they represent and by whose shed blood makes all rites and ordinances effectual, but they must also act by the power of the Holy Ghost which depends upon the the individual Bishop or Deacons relationship with God.
So the keys and authority of the priesthood turn us to Christ because we have to empower that authority by the Holy Ghost. Priesthood is the authority but the Holy Ghost is the power by Christ whose sacrifice makes it all possible. So when the Elders of Christs church anoint and heal the sick, they do it in the name of Christ, by the authority of the priesthood, and by the power of the Holy Ghost. This is why elders will often pray and fast and ask Christ for grace before the blessing, because they individually need the Holy Ghost to empower their authority. Without the empowerment of authority, the authority itself is ineffectual.
Is there an example of this principle in the Bible? Yes! Christ promised his disciples that if they had faith, their authority could move mountains. Yet, when they tried to cast out a devil they failed. What happened? They failed, because having priesthood authority alone is not enough. Christ then explained that the disciples failed because "these come not out without prayer and fasting." What was Christ teaching? He was teaching them that they needed to empower their authority by better receiving the Holy Ghost which depends on establishing a closer individual relationship with God by prayer and fasting. Christ is the best example of this principle. Christ fasted and prayed 40 days to empower his ministry and authority.
Mark 9: 28-29 And when he was come into the house, his disciples asked him privately, Why could not we cast him out? And he said unto them, This kind can come forth by nothing, but by prayer and fasting.
Lastly, why do you need priesthood keys and authority when every individual member is given the given the gift of the Holy Ghost? This is a critical point. Every true believer in Christ is given the power of the Holy Ghost and that power is just as powerful as the power Moses, Peter or any prophet or apostle had. Anyone with faith in Christ, through the power of the Holy Ghost alone could move mountains and perform miracles and receive revelation. Then why is priesthood necessary? While you could enjoy the blessings of your faith in Christ, you wouldn't have the authority to bless and administer to others. And that is what the Priesthood is. It is the authority to elicit the same blessings, miracles, and revelation by the power of the Holy Ghost, but on behalf of others. Unfortunately, some always want to create false dichotomies. They want to say that the Bible only speaks about Priesthood or only speaks about the Holy Ghost. The truth is Christ taught the Priesthood is the authority and the Holy Ghost is the power and together, through Christ, we can help and bless each other to better lift the hands that hang down and strengthen the feeble knees, visit the fatherless and widows, and keep ourselves unspotted from the world.