The following is an excerpt from The MacArthur New Testament Commentary on 1 Thessalonians 5:9-11.

For God has not destined us for wrath, but for obtaining salvation through our Lord Jesus Christ, who died for us, so that whether we are awake or asleep, we will live together with Him. Therefore encourage one another and build up one another, just as you also are doing. (1 Thessalonians 5:9–11)

The most sobering truth in Scripture is that God will judge the wicked and sentence them to eternal hell (Matt. 3:12; 25:41, 46; John 3:36; 5:29; Acts 24:25; Rom. 2:5, 8; 2 Thess. 1:9; Heb. 6:2; 2 Peter 2:9; 3:7; Rev. 14:9–11). On the other hand, the blessed truth for believers is that God has not destined us for wrath (cf. 1:10; John 3:18, 36; 5:24; Rom. 5:1, 9; 8:1, 33–34). Like their nature, established in the past at salvation, and their present pattern of obedience, day people’s future destiny sets them apart from night people. Believers will not experience the wrath God will pour out on unbelievers on the Day of the Lord, and for eternity in hell.

The word destined expresses the inexorable outworking of God’s sovereign plan for believers’ salvation. In Matthew 25:34 Jesus promised that believers will “inherit the kingdom prepared for [them] from the foundation of the world.” To the Ephesians Paul wrote, “He chose us in Him before the foundation of the world, that we would be holy and blameless before Him” (Eph. 1:4), while in 2 Timothy 1:9 he added, “[God] has saved us and called us with a holy calling, not according to our works, but according to His own purpose and grace which was granted us in Christ Jesus from all eternity.”

Orge (wrath) does not refer to a momentary outburst of rage, but to “an abiding and settled habit of mind” (Richard C. Trench, Synonyms of the New Testament [reprint; Grand Rapids: Eerdmans, 1983], 131). It is a general reference to the final judgment, when God’s wrath will be poured out on the wicked (Matt. 3:7; John 3:36; Rom. 1:18; 2:5, 8; 3:5; 4:15; 5:9; 9:22; 12:19; Eph. 5:6; Col. 3:6; Rev. 14:9–11). But God’s wrath here must also include the Day of the Lord, since that was the Thessalonians’ primary concern. Paul assured them that they would face neither temporal wrath on the Day of the Lord (cf. Rev. 6:17), nor eternal wrath in hell.

But—in contrast to the doomed night people—God has destined believers for obtaining (lit., “gaining,” or “acquiring”) salvation through our Lord Jesus Christ. Once again, Paul referred to the future dimension of believers’ salvation, their glorification (see the discussion of verse 8 above). But all three aspects of salvation—justification (Isa. 53:11; Rom. 3:24, 26; 5:8–9; 1 Cor. 6:11; Gal. 2:16), sanctification (1 Cor. 1:30; 6:11; Heb. 7:25), and glorification (cf. Phil. 3:21)—come only through our Lord Jesus Christ. The simple, yet profound phrase who died for (huper; “on our behalf”; “with reference to us”; “in our place”; “as our substitute”) us (cf. Rom. 5:8) expresses the sole basis for believers’ salvation. God “made Him who knew no sin to be sin on our behalf, so that we might become the righteousness of God in Him” (2 Cor. 5:21); “He Himself bore our sins in His body on the cross, so that we might die to sin and live to righteousness” (1 Peter 2:24; cf. John 10:11; Rom. 8:3; Gal. 1:4; 3:13; Eph. 5:2; 1 Peter 3:18; 1 John 2:2). The glorious message of the gospel is that Christ’s substitutionary death paid in full the penalty for believers’ sins and therefore believers will not face God’s judgment. In John 5:24 Jesus declared, “Truly, truly, I say to you, he who hears My word, and believes Him who sent Me, has eternal life, and does not come into judgment, but has passed out of death into life.” Nor will they face His condemnation, because “there is now no condemnation for those who are in Christ Jesus” (Rom. 8:1).

Christ’s death on their behalf sets all day people—both those who are awake (alive) and those who are asleep (dead; cf. 4:13–15)—apart from night people. The marvelous reality is that all believers will live together with Him, as Jesus Himself promised:

Do not let your heart be troubled; believe in God, believe also in Me. In My Father’s house are many dwelling places; if it were not so, I would have told you; for I go to prepare a place for you. If I go and prepare a place for you, I will come again and receive you to Myself, that where I am, there you may be also. (John 14:1–3; cf. 1 Thess. 4:17)

As he did with his discussion of the Rapture (cf. 4:18 where he used the same word rendered here “encourage”), Paul concluded his discussion of the Day of the Lord by exhorting the Thessalonians to encourage one another and build up one another. Based on the truth he had given them, they were to reassure the anxious and fearful that they would not experience the Day of the Lord. His concluding phrase, just as you also are doing, affirms that they were already committed to encouragement. Ever the faithful pastor, passionately concerned for his people, Paul wanted them to “excel still more” (4:1).