Jesus was, in Matthew 18, engaging in a time-honored rabbinical tradition: the linking of thoughts one to another, in a stream of consciousness. Sort of a Hebraic poetry format. Examples can be seen in other parts of the scriptures, e.g., Ecclesiastes, Proverbs, or in ancient rabbinical literature. Thus, there is no overarching “context” involved; only one with a Greek/Western/Hellenistic mindset would look for one in this type of passage.

Loosely put, Jesus starts his discussion with children and the Kingdom of God, then discusses abuse of children by evil people, what evil ones who lead little children astray ought to do with themselves (i.e., better to commit suicide), what to do with evil people in a church body context, how one ought to have two or three witnesses to confront them, then picking up on the two or three theme, how whatever we ask in the father’s name will be given if two or three are asking, then, again picking up the two/three theme, He states that God is with us when we’re gathered in grouops of two or three.

Each of these are timeless truths standing alone, they are linked only by theme, by common words or thoughts–-again, very much a Hebraic poetry format–-but not by overall context, to try to do so does violence to the truths Jesus was conveying.

These truths are not linked in a pedantic manner, such that the last “two or three” reference in verse 20 need be related to church discipline, evil doers, children, or suicide by drowning! We need to take the text for what it is, understanding that Jesus was an easterner speaking to easterners. His ministry was not to the gentiles, and He most certainly did not speak to them or their mindsets. For several sterling examples of transcendent truths put into linear and deductive western thought, see the Pauline epistles; don’t try to order Jesus’ thoughts around western logic, you will almost invariably come to the wrong conclusions.