The Lord said, “See that you do not despise one of these little ones; for I tell you that in heaven their angels always behold the face of My Father who is in heaven. What do you think? If a man has a hundred sheep, and one of them has gone astray, does he not leave the ninety-nine on the mountains and go in search of the one that went astray? And if he finds it, truly I say to you, he rejoices over it more than over the ninety-nine that never went astray. So it is not the will of My Father who is in heaven that one of these little ones should perish. If your brother sins against you, go and tell him his fault, between you and him alone. If he listens to you, you have gained your brother. But if he does not listen, take one or two others along with you, that every word may be confirmed by the evidence of two or three witnesses. If he refuses to listen them, tell it to the church; and if he refuses to listen even to the church, let him be to you as a Gentile and a tax collector. Truly, I say to you, whatever you bind on earth shall be bound in heaven and whatever you loose on earth shall be loosed in heaven. Again, I say to you, if two of you agree on earth about anything they ask, it will be done for them by My Father in heaven. For where two or three are gathered in My Name, there am I in the midst of them.
Matthew 18:10-20
Pentecost, as we know, commemorates the Descent of the Holy Spirit upon the Apostles, as tongues of fire, and allowed them to speak the Good News of the Gospel in all the languages of the world. Some say that the Church was established on Pentecost and most will agree that it is the Holy Spirit that leads the Church, continually bestowing grace and wisdom to both clergy and laity, as well as effecting all of the sacraments of the Church. It is the Holy Spirit Whom we call down upon our services, in our sacraments, and in prayer.
The day after Pentecost is called both the “Feast of the Holy Trinity” and the “Monday of the Holy Spirit.” The Gospel lesson gives us some guidelines on how the Church should conduct itself. First, Christ tells us that that we should not despise any of “these little ones.” (Matthew 18:10) This is in reference to what comes directly before today’s passage, when Christ tells His followers that they need to “become like children” (18:3) in order to enter the Kingdom of God. So, the Church is to include not only the adults, but the children. This is one, of many, reasons why the Orthodox Church extends full sacramental participation to the children and doesn’t wait for them to become adults.
Second, Christ tells us that there will be joy in heaven over a lost sheep who is found. Getting lost because of sin is something that happens to everyone. Christ reminds us that part of the mission of the Church is to find the lost sheep and return them to the flock. This takes patience on the part of the Church, as well as repentance on the part of the sheep who wants to be found and come back. He also tells us not to be haughty if we have not gone astray. There is more joy, says the Lord, over one sheep that is found than over ninety-nine that never went astray.
Third, Christ gives us a warning that there are some from inside the flock who will try to destroy the flock. These are not lost sheep, but antagonists, wolves, that seek to harm the flock. Christ gives us a formula for what to do about them. First, He tells us to go to our brother and try to correct the wrong between the two people. This is important. Many people skip this step—they go to everyone else and gossip about a problem without confronting the person who created it, who sometimes doesn’t even know they’ve done anything wrong. We should remember that when someone does wrong to us, the best course of action is usually to confront that person directly. (Of course, if the wrong perpetuated is a crime, like someone has physically harmed us, we should go to the authorities, not confront them. What we’re talking about here is the common disagreements we get into, especially in the church). If this does not work, if an antagonist in the church does not respond to a private confrontation, Christ tells us to “take one or two others with you” (18:16) so that what transpires will have witnesses to it. If this does not work, then Christ tells us to go to the church and tell a church authority, which might be a priest, the assembly of the community or the bishop. And if this doesn’t work, then the person may be excluded from the church. This is a last resort of course, but it is a Biblical recourse. There are antagonists in the church, who wish to do harm to the church, and who do harm to the church. The Church has to be mature enough to discern when someone is a lost sheep and when they are a wolf. The lost sheep is worth going to look for and there is great joy when the lost sheep is found. The wolf seeks to do harm and the flock must be protected from the wolf.
Fourth, Christ tells His disciples that whatever they bind on earth will be found in heaven and whatever they loose on earth will be loosed in heaven. Similar to the passage in John 20, where He tells the disciples that whatever sins they forgive are forgiven and whatever sins they retain are retained, the sacrament of confession has some of its foundational Scriptural beginnings in Matthew 18:18. Christ, through the Church, and through the Apostles, down to the present-day clergy, has provided a way for sins to be loosed so that the followers of Christ are not perpetually burdened with sin and guilt.
Finally, while the God can comfort anyone, even when they are alone, Matthew 18:20 establishes the number of people that are needed in order for a sacrament to take place. And the number is TWO.  “Where two or three are gathered in My name, there am I in the midst of them.”  All of the Sacraments take place in a corporate context. That means there are no private sacraments. The Divine Liturgy requires one celebrant bishop or priest and one person who is not the celebrant. There must be two people present. If a priest goes to the church to offer the Divine Liturgy and no one attends, there can be no Divine Liturgy. Likewise, there is no absolution of sins if there hasn’t been a confession where more than one person is present. In common practice, during confession, a priest and the penitent are present, two gathered in His name.
Blessed are You, O Christ our God. You made the fishermen all-wise, by sending down upon them the Holy Spirit, and through them You drew the world into Your net. O Lover of mankind, glory to You. (Apolytikion, Feast of Pentecost and the Holy Trinity, Trans. by Fr. Seraphim Dedes)
A close study of Scripture gives us great insight into the Traditions of the Church as well as guidelines for how we are to conduct ourselves in the Church. Because everything in our Church has its basis in Scripture.