1 Thessalonians 5:18

To the Christian who really trusts his Father's providence, and believes that his prayers are heard, every moment's occurrence will be just that which he has prayed for the fulfillment of our Father's will. It is for this reason that thanksgiving is so inseparably joined with prayer. (Philippians 4:6; Colossians 4:2.).

In everything give thanks. In every circumstance - in joy and in sorrow; for everything, for prosperity and for adversity, in every place - in the house of God and on the bed of sickness; Christians should not only be engaged in constant prayer, but in constant thanksgiving; indeed, their prayers should partake largely of the nature of thanksgiving. For this; this thankful spirit. Is the will of God; his desire. In Christ Jesus; the sphere in which this will of God is displayed. Concerning you. God by the gift of his Son has laid us under the obligation of perpetual thanksgiving. Our whole lives ought to be one continued thank-offering for all the blessings of redemption.

In everything give thanks, That is, to God the Father, in the name of Christ; see Ephesians 5:20 thanks are to be given to him for all things, as the Ethiopic version renders it; for all temporal good things; for our beings, the preservation of them; for food and raiment, and all the mercies of life; for the means of grace, the word and ordinances, and the ministers of the Gospel; for spiritual blessings, for electing, redeeming, regenerating, adopting, pardoning, justifying, and persevering grace: for a meetness for heaven, a right unto it, and a good hope of it; and especially for Jesus Christ, for such an husband, such an head, such a surety and Savior, and advocate with the Father, as he is; and for life, peace, joy, comfort, righteousness, and salvation in him: and thanks should be given to God in every circumstance of life; in adversity, as Job did; when not in so comfortable and agreeable a frame of soul as to be wished for, since it might be worse, and is not black despair; even under the temptations of Satan, since they might be greater and heavier, and since the grace of God is sufficient to bear up under them, and deliver out of them, and since there is such a sympathizing high priest and Savior, and in afflictions of every kind, since they are all for good, temporal, or spiritual, or eternal.

For this is the will of God; which may refer either to all that is said from 1 Thessalonians 5:11 to this passage, or particularly to this of giving thanks; which is the revealed and declared will of God, is a part of that good, perfect, and acceptable will of his, and what is well pleasing in his sight, and grateful to him; Psalm 69:30 and is in Christ Jesus concerning you; either declared in and by him, who has made known the whole of the will of God, and so the Arabic version, "which he wills of you by Jesus Christ"; or which is exemplified in Christ, who for, and in all things, gave thanks to God, and had his will resigned to his in every circumstance of life; or, which being done, is acceptable to God through Christ. The Alexandrian copy reads, "for this is the will of God towards you in Christ Jesus"; that is, with respect to you who are in Christ secretly by election, and openly by the effectual calling; and who, of all men in the world, have reason to be thankful for everything, and in every circumstance.
Reference
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