Ancient biographers sometimes praised the miraculous births of their subjects (especially prominent in the Old Testa ment), but there are no close parallels to the virgin birth. Greeks told stories of gods impregnating women, but the text indicates that Mary’s conception was not sexual; nor does the Old Testament (or Jewish tradition) ascribe sexual characteristics to God. Many miraculous birth stories in the ancient world (including Jewish accounts, e.g., 1 Enoch 106) are heavily embroidered with mythical imagery (e.g., babies filling houses with light), in contrast with the straightforward narrative style of this passage.
1:18. Betrothal (erusin) then was more binding than most engagements are today and was normally accompanied by the groom’s payment of at least part of the bride price. Betrothal, which commonly lasted a year, meant that bride and groom were officially pledged to each other but had not yet consummated the marriage; advances toward anyone else were thus regarded as adulterous (Deut 22:23-27). Two witnesses, mutual consent (normally) and the groom’s declaration were necessary to establish Jewish betrothals (in Roman betrothals, consent alone sufficed).
Mary would have probably been between the ages of twelve and fourteen (sixteen at the oldest), Joseph perhaps between eighteen and twenty; their parents likely arranged their marriage, with Mary and Joseph’s consent. Premarital privacy between betrothed persons was permitted in Judea but apparently frowned upon in Galilee, so Mary and Joseph may well not have had any time alone together at this point.
1:19. The penalty for adultery under Old Testament law was death by stoning, and this penalty applied to infidelity during betrothal as well (Deut 22:23-24). In New Testament times, Joseph would have merely been required to divorce Mary and expose her to shame; the death penalty was rarely if ever executed for this offense. (Betrothals were so binding that if a woman’s fiancé died, she was considered a widow; betrothals could otherwise be terminated only by divorce.) But a woman with a child, divorced for such infidelity, would be hard pressed ever to find another husband, leaving her without means of support if her parents died.
But because divorces could be effected by a simple document with two witnesses, Joseph could have divorced her without making her shame more widely known. (It was necessary to involve a judge only if the wife were the one requesting that the husband divorce her.) Much later rabbinic tradition charges that Mary slept with another man, but Joseph’s marrying her (v. 24) demonstrates that he did not believe this was the case.
1:24-25. Joseph acts like Old Testament men and women of God who obeyed God’s call even when it went against all human common sense. Marriage consisted of covenant (at the betrothal; the marital contract also involved a monetary transaction between families), a ceremony and consummation, which ratified the marriage, normally on the first night of the seven-day wedding. Joseph here officially marries Mary but abstains from consummating the marriage until after Jesus is born. Jewish teachers thought that men had to marry young because they could not resist temptation (many even blamed a woman’s uncovered hair for inducing lust). Joseph, who lives with Mary but exercises self-control, thus provides a strong role model for sexual purity.
(Adapted from The IVP Bible Background Commentary: New Testament. Buy the book here.)