(20) Where two or three . . .--The true meaning of the words is well embodied in the well-known patristic axiom, Ubi tres, ibi Ecclesia ("Where three are there is a church"). The strength of the Christian society was not to be measured by a numerical standard, but by its fulfilment of the true conditions of its life. The presence of Christ was as true and mighty, His communion with His Church as real, when His followers were but as a remnant, as when they were gathered in the great congregation. He would be with the "two or three" (there is, perhaps, a special reference to the self-same words in Matthew 18:16), to plead for them as the great High Priest, to impart Himself to them, to ratify their decisions.

Verse 20. - The promise is applied to the public prayer of the congregation, as we see in what is called "the prayer of St. Chrysostom" in the English Prayer book. Are gathered together. For the purpose of worship. It is a simpler form of the word used in Hebrews 10:25, "Not forsaking the assembling of ourselves together." In my Name (εἰς τὸ ἐμὸν ὄνομα); literally, into my Name; i.e. with love to me, yearning for union with me, and acting for my glory. This would imply decent and orderly meeting for the highest ends. There am I in the midst of them. Christ promises a real, actual presence, though invisible, as true as when he appeared to his disciples after his resurrection, as true as when the Shechinah shone in tabernacle or temple. The rabbis had a saying that if two sat at table and conversed about the Law of God, the Shechinah rested upon them. The promise in the text, of course, implies Christ's omnipresence and omniscience. This is his blessing on united, congregational prayer.

18:15-20 If a professed Christian is wronged by another, he ought not to complain of it to others, as is often done merely upon report, but to go to the offender privately, state the matter kindly, and show him his conduct. This would generally have all the desired effect with a true Christian, and the parties would be reconciled. The principles of these rules may be practised every where, and under all circumstances, though they are too much neglected by all. But how few try the method which Christ has expressly enjoined to all his disciples! In all our proceedings we should seek direction in prayer; we cannot too highly prize the promises of God. Wherever and whenever we meet in the name of Christ, we should consider him as present in the midst of us.For where two or three are gathered together,.... This seems to be said in opposition to a Jewish notion, that a number less than ten, is not a congregation (a); whereas, though the number is ever so few that are met together to pray to God; or to hear his word, attend on his ordinances, or do the business of his house, or transact any affair that is for the glory of God, and the good of souls, in my name, says Christ; that is, by his authority, depending on his assistance, calling upon his name, and making use of it, and seeking the glory of it:

there am I in the midst of them; presiding over them, ruling in their hearts, directing their counsels, assisting them in all they are concerned, confirming what they do, and giving a blessing and success to all they are engaged in. The Jews, though they say there is no congregation less than ten, yet own that the divine presence may be with a lesser number, even as small an one as here mentioned (b).

"Ten that sit and study in the law, the Shechaniah dwells among them, as it is said, Psalm 82:1. From whence does this appear, if but five? from Amos 9:6, from whence, if but three? from Psalm 82:1, from whence, if but two? from Malachi 3:16, from whence, if but one? from Exodus 20:24.''

And again (c),

"two that sit together, and the words of the law are between them, the Shechaniah dwells among them, according to Malachi 3:16, from whence does it appear, that if but one sits and studies in the law, the holy blessed God hath fixed a reward for him? from Lamentations 3:28.''

(a) Misn. Sanhedrim, c. 1. sect. 6. T. Bab. Megilia, fol. 23. 2. Gloss. in ib. (b) Pirke Abot, c. 3. sect. 6. (c) Ib. sect. 2.