In Mattthew's Gospel, 'bethrothal' differs greatly from 'engagement'. Among Jews, even children could be 'engaged'. Only adults were'bethrothed' one year before they were married. During this period they were regarded as 'husband and wife', but without marital rights. If one party proved unfaithful, 'divorce' was called for, and even death (Dt. 22:23-24).

This was the predicament Joseph faced when he found Mary pregnant. He would not pretend that Mary's child was his, and decided to divorce her secretly. Everything changed when an angel told him that Mary had conceived by the Holy Spirit, and that as legal father, he should name the child 'Jesus' who would save His people from their sins.

God's plan went beyond saving us from sin to making us His children. For this purpose God the Son became man. To emphasize His divine nature He was formed in Mary's womb not by a human father, but by God's power. Being truly God and truly man, Jesus could show us how to live as God's children.

Matthew sees all this as fulfilling the prophecy: "The virgin is with child and will give birth to a son, whom they will call Emmanuel which means 'God-with-us'."