(19) Shall agree on earth.--The promise, as before, is dependent on implied conditions. Those who pray must be gathered together in the name of Christ (Matthew 18:20), i.e., as trusting to His intercession, asking a prayer which is not the utterance of the natural but the spiritual man, asking it in entire submission to the will of their Father in heaven. In the absence of those conditions, as in the prayer of the sons of Zebedee, asking they knew not what (Matthew 20:20), that which they desired might be withheld from them, or granted in quite another manner than that on which they had set their hearts.

Verse 19. - Again I say unto you. The following paragraph has been thought by many to be addressed especially to the apostles in confirmation of the powers conferred on them above; but from ver. 20 we should judge the promise to be general. Herein is set forth the privilege of united prayer. God confirms the sentence of his authorized ambassadors; he gives special heed to the joint intercessions of all Christians. Two of you. Two of my followers, even the smallest number that could form an association. Shall agree (συμφωνήσωσιν). Be in complete accord, like the notes of a perfect strain of music. Here one man's infirmity is upheld by another's strength; one man's short-sightedness compensated by another's wider view; this man's little faith overpowered by that man's firm confidence. Anything. Of course, this is to be understood with some restriction. The thing asked must be reasonable, good in itself, expedient for the petitioner; the prayer must be earnest, faithful, persevering. If such conditions are satisfied, the desire will be granted in some form, though, perhaps, not in the way or at the time expected. Thus the Lord sanctions guilds or bodies of Christians united together to offer up supplications for special objects or with some definite intention in which all ere agreed.

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.Again, I say unto you,.... As the words in the former verse seem to regard the whole body of the disciples, whose decisions in cases brought before them, declaring them just or unjust, are determinate and unalterable; these seem to respect the one or two, that should join the offended person in the reproof of the offender, and are spoken for their encouragement; who might think proper either to premise, or follow their engaging in such a work with prayer:

that if two of you shall agree on earth, as touching anything that they shall ask; both in the case before mentioned, and in any other thing: whether it be for themselves or others; to assist them in the ministry of the word, and give success to it, for the conversion of sinners; and in the performance of any miracle, for the confirmation of the Gospel; in the administration of ordinances, for the comfort of saints; and in laying on of censures, for the reclaiming of backsliders; or be it what it will that may be done, consistent with the glory of God, the purposes of his mind, and the declarations of his will, and the good of men, provided they agree in their requests; though they are here on earth, and at such a distance from heaven, from whence their help and assistance come:

it shall be done for them of my Father which is in heaven; with whom nothing is impossible; and who, as he regards the effectual fervent prayer of any righteous man, so more, of two agreed together in anyone thing; and still more, of a church and community of saints in their united requests: a great encouragement this to social prayer, though ever so few are engaged in it.