v. 18. In everything give thanks; for this is the will of God in Christ Jesus concerning you.
v. 19. Quench not the Spirit.
v. 20. Despise not prophesyings.
v. 21. prove all things; hold fast that which is good.
v. 22. Abstain from all appearance of evil.
Of these brief admonitions one commentator says: "To comment adequately upon these diamond drops would be to outline a history of the Christian experience in its higher levels. " Always to rejoice is a characteristic of all Christians, even in poverty, sickness, misery, persecution, and whatever other mischance befall them, for they know that all things work together for good to them that love God, Rom_8:28. As far as the attitude toward God is concerned, it cannot be anything but joyful. It is not easy, of course, for weak flesh and blood to reach this level, but the Christian has the remedy and the tonic all in one: Without ceasing pray. Believers, as children of God in Christ Jesus, have the habit of praying, of bringing all their needs to their heavenly Father. The apostle does not merely urge regularity in the practice of prayer, but he wants our hearts always to be disposed toward prayer, always in the mood to make all our wants known to Him who never fails His children. There must be a constant spirit of prayer breathing through the Christian's whole life. Incidentally, no prayer should be offered without thanksgiving, express or implied; every petition should be accompanied by thanksgiving, for the gift will surely be forthcoming if the prayer is made in faith, according to the will of God, The fulfillment may not agree with the form of our petition, but it surely is always in line with our needs; and so the will of God toward us in Christ Jesus, our Savior, is that we practice the giving of thanks at all times, in all things.
The apostle now passes on to the source from which prayer and thanksgiving flow, admonishing the Christians not to quench or oppress the Spirit, The Holy Ghost, received as a gift of God through the Word, works in the hearts of the Christians, distributing various gifts of grace, making intercession for us with groanings which cannot be uttered, Rom_8:26. To resist the influence of the Spirit, to grieve Him in His work, either by ingratitude or by any ever so slight transgression of the will of God, means to render His work ineffectual and even to drive Him out of the heart. For that reason the Thessalonian Christians mere also not to disdain and despise prophetic revelations wherever they are given, since they are the work of the Spirit. Whenever a Christian, under this special influence of the Spirit, with this special gift, had a message to the Church, an explanation of some divine truth, especially with reference to the future, his proclamation should be received with all due respect. This does not mean, however, that every message purporting to be a prophecy should be accepted blindly and without judgment. All things prove, the good accept, the apostle says. We should apply a test, the test of the Word of God, to all matters that are presented for our consideration and for our acceptance, after the example of the Bereans, Act_17:11. And what, according to this criterion, is found excellent, that we should hold fast, that we should cling to, that we should retain. At the same time, of course, we should abstain from everything that appears to be wickedness or from every kind of evil, even from the apparently spiritual form, in doctrine as well as in conduct. So many forms of evil, particularly in our days, appear under the guise of the greatest good, under a sacred pretense, that it requires the most careful application of the standard given by the Word of God to detect the swindle and to remain uncontaminated. There are few pious frauds in our days that do not find ready acceptance, as the increasing number of sects plainly indicates.