9 But concerning brotherly love you have no need that I should write to you, for you yourselves are taught by God to love one another;
10 and indeed you do so toward all the brethren who are in all Macedonia. But we urge you, brethren, that you increase more and more;
11 that you also aspire to lead a quiet life, to mind your own business, and to work with your own hands, as we commanded you,
12 that you may walk properly toward those who are outside, and that you may lack nothing.
no need that I should write to you (v.9) — They were already showing brotherly love. But this also seems to be Paul’s way of saying that they weren’t already following his teachings on sexual purity.
taught by God (v.9) = theodidaktoi, lit. “God-taught persons”
love (v.9, 2nd use) = agape
increase more and more (v.10) — 1 Thessalonians 3:12
aspire (v.10) = make it your ambition, strive restlessly after — The Greek word is translated “made it my aim” in Romans 15:20 and 2 Corinthians 5:9.
quiet (v.11) = to be at rest
lead a quiet life (v.11) — 2 Thessalonians 3:12
mind your own business (v.11) — 2 Thessalonians 3:11
At Thessalonica, apparently, the “trivial round, the common task,” was neglected by some on the plea of the superior claims of religion, a vicious idea that has wrought much mischief since, notwithstanding its emphatic and repeated repudiation by the apostle, cp. Titus 3:14.
The life of the Christian cannot be divided as into secular and sacred, cp. Colossians 3:23-24, the whole is to be lived for God always. Moreover, idlers, neglecting their own, easily become “meddlers in other men’s matters,” lit., “overseers of others’ concerns,” 1 Peter 4:15, and not infrequently indolent dependents on other men’s bounty as well. — Vine, page 61.
work with your own hands (v.11) — In many pagan religions, there is a large priesthood who do no work but rely entirely upon the largess of others to live. Paul preached against this both in words and in person example (Acts 18:1-3). In the Thessalonians’ case, apparently some were so fired up about the return of Christ that they stopped working, making it necessary for others to provide for them.
honestly (v.12) = becomingly, decently
that you may lack nothing (v.12) — so that they can provide for the needs of themselves and their families (1 Timothy 5:8). Paul wrote more on this in 2 Thessalonians 3:6-15.
Perhaps Timothy had reported to him [Paul] an incipient tendency on the part of some to forbear working and to become busybodies (See 2 Thessalonians 3:11-12). It may be that they felt they were justified in just waiting for the Lord to come. In any case, the Apostle urges them to study to be quiet, to mind their own business, as we say, and to “eat their own bread” (v.12) And all this, that they might “walk honestly toward them that are without,” and “have lack of nothing. If they should not heed his exhortation they might well soon find themselves lacking the necessities of life and owing bills to “them that are without.” Such lack of integrity and self-reliance can only dishonor God and the message He has committed t our trust.
How wholesome and down-to-earth are the Apostle’s exhortations here as to integrity, industry and self-reliance, and what respect such conduct is bound to earn for one who would be used of God. — Stam, page 57.