It is often said at the end of a small group with half the chairs empty: where two or three are gathered. The quotation is exact. What it closes, in Matthew, is a set of steps for winning back someone who has wronged you. You go to him alone first, and if he will not hear you, you take one or two more, so that two or three stand as witnesses. Jesus promises to be in the middle of that.
Word for word, in its paragraph
For where two or three are gathered together in my name, there am I in the midst of them.
Matthew 18:20 (KJV)
The words are right. What gets lost is the paragraph around them.
The chapter starts with the disciples asking who is the greatest, and Jesus setting a little child in the middle of them. Ten verses later he tells the story of a man with a hundred sheep who leaves the ninety-nine to look for the one that wandered off, and then applies it: “Even so it is not the will of your Father which is in heaven, that one of these little ones should perish,” in Matthew 18:14. The next words are about one person.
Moreover if thy brother shall trespass against thee, go and tell him his fault between thee and him alone: if he shall hear thee, thou hast gained thy brother. But if he will not hear thee, then take with thee one or two more, that in the mouth of two or three witnesses every word may be established.
Matthew 18:15-16 (KJV)
Count the people on the second visit. You, and one or two more. That makes two or three, and you are one of them.
The steps, in order
The number is the law’s. Deuteronomy 19:15 says that “at the mouth of two witnesses, or at the mouth of three witnesses, shall the matter be established,” and Jesus is applying that rule to a quarrel between believers. Paul uses the same formula in 2 Corinthians 13:1 and in 1 Timothy 5:19, and both times the subject is discipline in the church.
Then come the last steps. In verse 17, if the brother will not hear the two or three, the church hears the matter, and if he will not hear the church, he is to be to you “as an heathen man and a publican.” In verse 18 Jesus gives the church authority over what it decides: “Whatsoever ye shall bind on earth shall be bound in heaven: and whatsoever ye shall loose on earth shall be loosed in heaven.” Then comes the verse about asking.
Again I say unto you, That if two of you shall agree on earth as touching any thing that they shall ask, it shall be done for them of my Father which is in heaven.
Matthew 18:19 (KJV)
Verse twenty explains verse nineteen. The Father answers because Jesus is there with them.
Is this verse about prayer, then?
Partly. Verse nineteen is a promise about asking, and it is broad: “any thing that they shall ask.” But it is given inside the steps, to people who have just been told to go after a brother and get him back. Its first use is one of the hardest conversations a church has.
The comfort for a thin meeting is not lost. It comes from a different verse. In Matthew 28:20, as Jesus sends his disciples out, he says, “lo, I am with you alway, even unto the end of the world.” A small group of his people is not outside that promise. Matthew 18:20 is something more specific: a promise to the two or three on their way to a door they would rather not knock on.
Step one
Step one is to go to him yourself and tell him his fault between you and him alone, not to tell the group first. Jesus gives that instruction for a brother who has wronged you, and the steps fit a sister just as well. The private talk is about a wrong done to you, not a verdict on how someone else lives. Going may cost you a friendship, and in a small group that can feel like losing a third of the room. The point of going is the one Jesus names: “thou hast gained thy brother.” If the person is dangerous, go first to the people who can protect you; nothing in these verses sends anyone alone into harm.
In Matthew 7:5 Jesus tells you to deal with your own eye first, and then to help your brother with his. The paragraph on “judge not” ends with you close enough to do it, and this is the errand it sends you on.
The paragraph is the lost sheep written out as a procedure: go after the one, go alone first, and if that fails take one or two more and go again. Peter’s question comes right after it, how many times he must forgive a brother who keeps doing it, and the answer is “Until seventy times seven.” Go and get him, says the chapter, and when you have got him, forgive him.
If a brother has wronged you, and it is safe to sit down with him, the first step in Matthew 18 is a conversation between the two of you, before the group hears a word. It is the shepherd’s errand from earlier in the chapter, going after the one, and in verse 15 it is given to you.