Main principle: each person should live as a believer in whatever situation the Lord has assigned to them, just as God has called them (17; 20; 24). Being a Christian means bringing what one IS into the service of God.

Illustration # 1: circumcision (18–20)

To the circumcised: do not change (18a)
To the uncircumcised: do not change (18b)
Reason: neither counts, just keeping the commands of God (19)
Conclusion: stay in your “calling” (20)

Illustration # 2: slavery (21–24)

To the slave: do not be concerned (21a)
Exception: If granted, make use of freedom (21b)
Reason: (1) to slave: one is Christ’s freedman (22a)
(2) to free person: one is Christ’s slave (22b)

You were bought at a price; do not become slaves of human beings (23)

Conclusion: stay in your “calling” with God (24)

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vv. 1–7: to the married: stay married with full conjugal rights
vv. 8–9: to the “unmarried” and widows: it is good to remain unmarried
vv. 10–11: to the married (both partners believers): remain married
vv. 12–16: to those with an unbelieving spouse: remain married

vv. 17–24: “On matters related to slavery and circumcision: Remain in the place you were at the time of your call.”

vv. 25–38— to “virgins”: it is good to remain unmarried
vv. 39–40— to married women (and widows): the married are bound to the marriage; when widowed it is good to remain that way