Continuing the subject of the "Day of the Lord" (5:2-3), the apostle shows the way in which believers should prepare for that day, remembering that it will come suddenly, without any sign, with the Rapture of the Church. Our conduct must show expectation with vigilance and sanctification.
"Sons of light" and "children of the day" - this means that believers in Christ already know that, suddenly, He will come to take to heaven the remainder of His Church on earth and then the Day ( period) of judgement will start over the earth (v.4-5).
Our conduct, then, should correspond with such knowledge and hope. The world in general does not expect, nor behaves as if it expected, the Coming of Christ or the Lord's Day. They are "children of darkness", sleeping, walking in their sins as if there were no God, without need to prepare to give him account.
We see once again, the three special qualities of Christian character - faith, love and hope (v.8). Practicing these virtues, we will show that we are "children of light”, not intended for divine wrath, but rather to eternal salvation, and so we walk in fellowship with Him.
So we may comfort ourselves and edify each other, in the joy of His love and in the expectation of His coming (v.9-11).
In this section, we have brief exhortations, dealing with various aspects of Christian life.
Elders should be recognized, honoured and loved, because of their important work to guide, teach and advise believers (v.12-13). Their administration of the church should not be disputed or disobeyed; they are responsible to God for the work they do, which is not at all easy. "Live in peace"- for the welfare of a church depends upon the wholehearted cooperation of all members.
It seems that the exhortations in verses 14 and 15 are addressed to the elders and spiritually mature believers in the local church. They have to admonish (warn, rebuke) the unruly, disruptive and lazy - see the 2 Thessalonians 3:6-12. The strong ones need to encourage the discouraged and help the weak in faith. All this with patience, for God is longsuffering - see Romans 2:4, 9:22, 1 Peter 3:20. You should never find a vindictive spirit in believers, wishing to pay evil with evil, for the Lord forbids it (Matthew 5:39-46).
Rejoicing, prayer and thanksgiving (v.16-18) must be constant features of Christians, even in time of persecution or great difficulty. See Matthew 5:12, Luke 10:20-21, Romans 5:12, James 1:9 and Philippians 1:18.
Christian joy is not extinguished in the midst of distress or hard circumstances because it is related to our union with God (Philippians 2:18, 3:1, 4:4).
"Prayer without ceasing" does not mean very long prayers, which tire the congregation, but refers to an attitude of constant devotion to God, which shows itself in worship, praise and petition.
Gratitude (v. 18) must also be constant in the believer - we have so many blessings, day after day, for which we should give thanks, including difficulties and afflictions - "in everything give thanks "...
"Do not quench the Spirit" (v.19). It seems that this prohibition refers to the overall work of the Holy Spirit in Christian life, as He teaches, guides, comforts, strengthens, and, in general, maintains the new divine nature that each believer has received in his conversion (Romans 8:11; 2 Timothy 1:14).
Perhaps there is also reference to the special gifts of the Holy Spirit, which can be "quenched" by negligence (1 Timothy 4:14, 2 Timothy 1:6). In addition, you can quench, or at least prevent the operation of the Spirit in another brother through dissuading him from following what he knows to be God's guidance (see a sad example of this in the 1 Kings 13:15 - 19, where a young prophet was diverted from his path by an old man - with tragic results). Also the voice of the Spirit can be prevented, and even erased, by the constant practice of sin, and thus His fruit will not be produced in the life of the believer (Galatians 5:22-26).
"Do not despise prophecies" (v.20). "Prophecy" can mean the teaching given regularly in the church; or predictions given by special revelation (1 Corinthians 12:10, 13:2) and, of course, includes the prophecies written in both Testaments of the Bible. Let us study these and also take advantage of the explanations given by the Holy Spirit to brethren of trust.
However, we do not have to accept everything that is offered as a prophecy or teaching (v.21). There are false teachers and deceivers in this world, and also wrong doctrines commonly accepted as truth and teachings that are a mixture of truth and error. The believer must examine carefully all teaching, accept what agrees with the Scriptures and reject every kind of falsehood in doctrine or practice (v.22).
The power for the believer's sanctification is God Himself (v.23-24). He called us to be His "holy people" (1 Peter 2:9) and He will faithfully fulfil that purpose in us, through the Holy Spirit and the Bible, so as to be found perfectly blameless at the Coming of the Lord.
The Apostle asks for the prayers of his converts; how much more should we pray for the preachers and teachers in our churches! The greetings of believers should be sincere and earnest (v.26). The letter was for all members of the church - not only for ministers! Also the divine grace (love, blessing and power of God) is for every believer (v.27-28).
4 But you, brethren, are not in darkness, so that this Day should overtake you as a thief.
5 You are all sons of light and sons of the day. We are not of the night nor of darkness.
6 Therefore let us not sleep, as others do, but let us watch and be sober.
7 For those who sleep, sleep at night, and those who get drunk are drunk at night.
8 But let us who are of the day be sober, putting on the breastplate of faith and love, and as a helmet the hope of salvation.
9 For God did not appoint us to wrath, but to obtain salvation through our Lord Jesus Christ,
10 who died for us, that whether we wake or sleep, we should live together with Him.
11 Therefore comfort each other and edify one another, just as you also are doing.
12 And we urge you, brethren, to recognize those who labor among you, and are over you in the Lord and admonish you,
13 and to esteem them very highly in love for their work's sake. Be at peace among yourselves.
14 Now we exhort you, brethren, warn those who are unruly, comfort the fainthearted, uphold the weak, be patient with all.
15 See that no one renders evil for evil to anyone, but always pursue what is good both for yourselves and for all.
16 Rejoice always,
17 pray without ceasing,
18 in everything give thanks; for this is the will of God in Christ Jesus for you.
19 Do not quench the Spirit.
20 Do not despise prophecies.
21 Test all things; hold fast what is good.
22 Abstain from every form of evil.
23 Now may the God of peace Himself sanctify you completely; and may your whole spirit, soul, and body be preserved blameless at the coming of our Lord Jesus Christ.
24 He who calls you is faithful, who also will do it.
25 Brethren, pray for us.
26 Greet all the brethren with a holy kiss.
27 I charge you by the Lord that this epistle be read to all the holy brethren.
28 The grace of our Lord Jesus Christ be with you. Amen.
1 Thessalonians chapter 5, verses 4 to 28