While in 1 Thessalonians 5:12-15 Paul in 1st Thessalonians 5:12-15 has shown what should be the attitude of the Thessalonians toward their leaders, to fellow-members characterized by particular shortcomings, to those who have injured them, and finally to one another and to all, in verses 16-18 he sets forth what should be their inner attitude and how this inner attitude should express itself with reference to God. Hence, we now have the following three beautiful closely related and tersely expressed admonitions: “Rejoice always, pray without ceasing, give thanks in all circumstances; for this is the will of God in Christ Jesus for you.”
The Thessalonians were no strangers to the “joy unspeakable and full of glory” (1 Peter 1:8), the “great joy” which results from the incarnation of Christ and from the redemption wrought through his cross. Yet with persecution from without and disturbances within, there was a danger (human speaking) that this joy would disappear. Hence, Paul, who himself again and again rejoiced in the midst of persecution and hardship (3:7-9; Phil 3:1; 4:4, 10), urges his readers to rejoice always.
In seasons of distress and grief he alone is able to find relief and even be joyful (Rom. 8:28, 35-39) who at the Father’s throne makes all his wants and wishes known. Hence, the directive “rejoice always” is immediately followed by “pray without ceasing.” What Paul means is there must be no decline in the regularity of the habit of “taking hold of God” In the midst of all circumstances of life. The apostle could afford to say this, for he himself gave the example (3:10; 2 Thess. 1:11; Eph. 1:16; 3:14).
When a person prays without giving thanks, he has clipped the wrings of prayer so that it cannot rise. Hence, the trio of admonitions concludes with, “give thanks in all circumstances.” This phrase in all includes affliction for even in the mist of all these things (“tribulations, anguish, persecution, famine, nakedness, peril of sword”) believes are not merely conquerors but “more than conquerors”, inasmuch as all these things actually help them to reach their goal (Rom. 8:35-37).
“For this is the will of God in Christ Jesus for you.” The will of God, as clearly set forth by means of the redemptive work and revelation of Jesus Christ, is this very thing, namely, that believers should always be joyful, should ceaselessly pray, and should in all circumstances give thanks.