I Thessalonians 5:18

In every thing give thanks - For this reason, that all things work together for good to them that love God; therefore, every occurrence may be a subject of gratitude and thankfulness. While ye live to God, prosperity and adversity will be equally helpful to you. For this is the will of God - That ye should be always happy; that ye should ever be in the spirit of prayer; and that ye should profit by every occurrence in life, and be continually grateful and obedient; for gratitude and obedience are inseparably connected.

In every thing--even what seems adverse: for nothing is really so (compare Rom 8:28; Eph 5:20). See Christ's example (Mat 15:36; Mat 26:27; Luk 10:21; Joh 11:41). this--That ye should "rejoice evermore, pray without ceasing, (and) in every thing give thanks," "is the will of God in Christ Jesus (as the Mediator and Revealer of that will, observed by those who are in Christ by faith, compare Phi 3:14) concerning you." God's will is the believer's law. LACHMANN rightly reads commas at the end of the three precepts (Th1 5:16-18), making "this" refer to all three.

Quench not the spirit. By which is meant, not the person of the Spirit, but either the graces of the spirit, which may be compared to light, and fire, and heat, to which the allusion is in the text; such as faith, which is a light in the soul, a seeing of the Son, and an evidence of things not seen; and love, which gives a vehement flame, which many waters cannot quench; and zeal, which is the boiling up of love, the fervency of it; and spiritual knowledge, which is also light, and of an increasing nature, and are all graces of the spirit: and though these cannot be totally extinguished, and utterly put out and lost, yet they may be greatly damped; the light of faith may become dim; and the flame of love be abated, and that wax cold; the heat of zeal may pass into lukewarmness, and an indifference of spirit; and the light of knowledge seem to decline instead of increasing; and all through indulging some sin or sins, by keeping ill company, and by neglecting the ordinances of God, prayer, preaching, and other institutions of the Gospel; wherefore such an exhortation is necessary to quicken saints, and stir them up to the use of those means, whereby those graces are cherished and preserved in their lively exercise; though rather the gifts of the Spirit are intended. The extraordinary gifts of the Spirit, bestowed on the apostles at the day of Pentecost, are represented under the symbol of fire, to which perhaps the apostle may here have respect; and the more ordinary gifts of the Spirit are such as are to be stirred up, as coals of fire are stirred up, in order that they may burn, and shine the brighter, and give both light and heat, Ti2 1:6 and which may be said to be quenched, when they are neglected, and lie by as useless; when they are wrapped up in a napkin, or hid i…

The apostle, having spoken in the end of the foregoing chapter concerning the resurrection, and the second coming of Christ, proceeds to speak concerning the uselessness of enquiring after the particular time of Christ's coming, which would be sudden and terrible to the wicked, but comfortable to the saints (Th1 5:1-5). He then exhorts them to the duties of watchfulness, sobriety, and the exercise of faith, love, and hope, as being suitable to their state (Th1 5:6-10). In the next words he exhorts them to several duties they owed to others, or to one another (Th1 5:11-15), afterwards to several other Christian duties of great importance (Th1 5:16-22), and then concludes this epistle (Th1 5:23-28).

5:18 Be thankful: God is sovereign and can redeem any situation (Rom 8:28).