1 Thessalonians 1:3

"Remembering without ceasing," he says, "your work of faith and labor of love and patience of hope in our Lord Jesus Christ, before our God and Father." What is remembering without ceasing? Either remembering before God and the Father, or remembering your labor of love that is before God and the Father, or simply, "Remembering you without ceasing." Then again, that you may not think that this "remembering you without ceasing" is said simply, he has added, "before our God and Father." And because no one amongst men was praising their actions, no one giving them any reward, he says this, "You labor before God." What is "the work of faith"? That nothing has turned aside your steadfastness. For this is the work of faith. If thou believest, suffer all things; if thou dost not suffer, thou dost not believe. For are not the things promised such, that he who believes would choose to suffer even ten thousand deaths? The kingdom of heaven is set before him, and immortality, and eternal life. He therefore who believes will suffer all things. Faith then is shown through his works. Justly might one have said, not merely did you believe, but through your works you manifested it, through your steadfastness, through your zeal.

And your labor "of love." Why? what labor is it to love? Merely to love is no labor at all. But to love genuinely is great labor. For tell me, when a thousand things are stirred up that would draw us from love, and we hold out against them all, is it not labor? For what did not these men suffer, that they might not revolt from their love? Did not they that warred against the Preaching go to Paul's host, and not having found him, drag Jason before the rulers of the city? (Acts xvii. 5, 6) Tell me, is this a slight labor, when the seed had not yet taken root, to endure so great a storm, so many trials? And they demanded security of him. And having given security, he says, Jason sent away Paul. Is this a small thing, tell me? Did not Jason expose himself to danger for him? and this he calls a labor of love, because they were thus bound to him.

And observe: first he mentions their good actions, then his own, that he may not seem to boast, nor yet to love them by anticipation. "And patience," he says. For that persecution was not confined to one time, but was continual, and they warred not only with Paul, the teacher, but with his disciples also. For if they were thus affected towards those who wrought miracles, those venerable men; what think you were their feelings towards those who dwelt among them, their fellow-citizens, who had all of a sudden revolted from them? Wherefore this also he testifies of them, saying, "For ye became imitators of the Churches of God which are in Judaea."

"And of hope," he says, "in our Lord Jesus Christ, before our God and Father." For all these things proceed from faith and hope, so that what happened to them showed not their fortitude only, but that they believed with full assurance in the rewards laid up for them. For on this account God permitted that persecutions should arise immediately, that no one might say, that the Preaching was established lightly or by flattery, and that their fervor might be shown, and that it was not human persuasion, but the power of God, that persuaded the souls of the believers, so that they were prepared even for ten thousand deaths, which would not have been the case, if the Preaching had not immediately been deeply fixed and remained unshaken.

And labor:
Now faith raises us to labors, and love causes us to remain in those labors.

And enduring hope:
And he says "enduring", because persecution is not a one time thing, but it is continuous. All these things, he says, do from faith and hope, so that those circumstances will not only show their courage, but with assurance they might trust in their future rewards. For this reason God allows persecution to occur, in order that their zeal might be shown, and that their conviction might not be seen as coming from themselves, but from the power of God, which persuades the souls of believers so that they be prepared to face a myriad of dangers. But if the Gospel was not steadfast among them they then would not be able to endure.

Not only, he says, do I remember you in prayers, but also at every other time. This is proof of his fervent love.

That is, your steadfastness. For the essence of faith is to stand firm, and not merely to boast of faith in words.

What labor is it to love? Simply to love is no labor; but to love truly is a great labor. For if someone endures all things for the sake of a beloved person, how is this not labor? And the Thessalonians indeed suffered much out of love for Paul, as can be seen from the book of Acts (Acts 17:5).

Much, he says, you endured in prolonged trials, and you endured, sustained by hope. For with full conviction you believed in the rewards prepared: since God allowed them at the beginning to undergo trials so that no one would say that the preaching was established simply and by flattery, but so that it would be evident that what was at work here was not human persuasion, but the power of God, subduing souls.

One can understand this in two ways: either remembering before God and our Father; or understanding "the work of faith" which is before God. So do not think that you labor in vain; on the contrary, everything is before God, and He will render the reward.

Then when he says, "remembering... your work of faith," Paul mentions the blessings for which he offers thanks, that is, faith, hope, and charity: "So faith, hope, love abide, these three" (1 Cor. 13:13). First, he mentions faith because it is an essential condition for obtaining the things to be hoped for, a means of revelation not based on appearances: "For whoever would draw near to God must believe that he exists and that he rewards those who seek him" (Heb. 11:6). This, however, is not sufficient unless the person practices good works and makes an effort; so Paul says, "your work of faith and labor." "Faith apart from works is dead" (Jas. 2:26). The person who gives up while laboring for Christ is worth nothing: "They believe for a while and in time of temptation fall away" (Lk. 8:13). Paul uses the words, "work" and "labor," implying that he is mindful of their active and struggling faith.

Paul also gives thanks for the love in which they abounded. Later (4:9), he says: "but concerning love of the brethren you have no need to have any one write to you."

Then he gives thanks for their hope, which enables them to endure sufferings patiently: "Rejoice in your hope, be patient in tribulation" (Rom. 12:12). In addition, Paul gives thanks for the steadfastness of their hope: "You have heard of the steadfastness of Job" (Jas. 5:11). Finally, Paul gives thanks for hope in our Lord, that is, the hope we have in Christ, or the hope Christ gave to us: "We have been born anew to a living hope through the resurrection of Jesus Christ from the dead" (1 Pet. 1:3). This hope is, "before our God," not before the eyes of men; "Beware of practicing your piety before men in order to be seen by them" (Matt. 6:1). "We have this as a sure and steadfast anchor of the soul" (Heb. 6:19). For hope in the old dispensation did not lead to God.