2 Thessalonians 1:3

We are bound to thank God
Since all blessings, temporal and spiritual, come from him: and that always: seeing he is ever giving out fresh favours, or continuing former ones; and because those, especially which are of a spiritual nature, always abide, such as faith and love; which the apostle particularly takes notice of, the members of this Church had, and were increasing in them: for it was not for himself, but for them he gives thanks,

for you, brethren:
who were so, not in a natural or civil relation, but in a spiritual one, being the children of God, and brethren of Christ; and to do this for them, he looked upon himself with others under an obligation:

as it is meet;
just, proper, and fitting; it not only becomes the persons who have received mercies from God to be thankful for them; but it is very right for others to join with them in it, and especially the ministers of the Gospel, who are bound, and whom it becomes: it is agreeable to their office and profession to give God the praise and glory of all the grace, and the increase of it, which those, who attend their labours, are favoured with, since this is not of them, but of God; and it was for an increase of grace the apostle here gives thanks, as he judged he was obliged to do, and it was fit he should.

Because that your faith groweth exceedingly.
Their faith was not a faith of miracles, nor a mere historical faith, or a counterfeit and temporary one, but the faith of God's elect; which is the evidence of things not seen, of an unseen Christ, and the glories of another world; that grace by which a man goes out of himself to Christ for righteousness, life, and salvation; by which he is justified, and by which he lives on Christ, and walks on in him as he has received him. This was theirs; it was not of themselves, the produce of nature, or the fruit of their natural power and free will; but it was the gift of God, and of his operation; a fruit of the Spirit of God, and of which Christ was the author and finisher; and was only theirs, as being given unto them, implanted in them, and exercised by them under the influence of the Spirit of God, and for their use, comfort, and advantage. This was, at first, but like a grain of mustard seed, very small, but gradually increased, and grew exceedingly; and from seeing of Christ, and looking at him, and which at first might be very dim and obscure, it proceeded to going or coming to him; and which might be in a very feeble manner, and was not without being drawn and led, and great encouragements, many invitations, and large assurances; and from thence to a laying hold upon him, though it may be but in a trembling way, and not without being called to stretch forth the hand of faith, and be no more faithless, but believing; and from thence to a leaning and relying on him, trusting in him with all, and for all; and from thence to claiming an interest in him, saying, my Lord, and my God, which is the full assurance of faith; and when it is come to this, it is grown exceedingly, which might be the case of these Thessalonians; which the apostle knew by the aboundings of their love, for faith works by love; and by their patience, firmness, and resolution in suffering for Christ; all which are in proportion to faith, and the growth of it; and for this he gives thanks to God, for faith is a precious thing; and as that itself, so the increase of it is from God, and therefore to him the praise belongs:

and the charity of everyone of you towards each other aboundeth;
as their faith in Christ, so their love to one another was increasing, and showed itself in serving one another both in temporals and spirituals; and this was not the case of a few only, or of the greater part, but of everyone of them; which made their communion with one another very comfortable and delightful. For what is more pleasant than for brethren to dwell together in unity?