He wasn’t! Though some describe Mary as being an unwed mother, even suggesting that Mary was in jeopardy of being stoned to death for adultery, the facts don’t support that contention. In Matthew, chapter one, we read:
“This is how the birth of Jesus the Messiah came about: His mother Mary was pledged to be married to Joseph, but before they came together, she was found to be pregnant through the Holy Spirit. Because Joseph her husband was faithful to the law, and yet did not want to expose her to public disgrace, he had in mind to divorce her quietly.”
As a follower of the law, Joseph could divorce his wife for any cause, but he couldn’t divorce someone to whom he was not married. Therefore we have to look more closely at the customs of the times and the meaning of the words used to describe this situation. Betrothal, translated here as “pledged to be married”, describes a legal agreement joining two people. This is quite different from what we today call an engagement because once betrothed, neither of the two could back out. A betrothal could only be broken by death or divorce. That they had “not come together” reflected a custom of the time that a pledged couple would remain apart for a period of time–often until a room is added to the home of the groom’s family to which the groom would ultimately bring his bride. That they did “not come together” also suggests that they were not intimate up until this time, that’s why the birth of Jesus is described as a virgin birth, or a conception without the seed of a man.
Would Mary’s pregnancy cause her to be marginalized or even result in her being stoned for adultery? No. Not unless Joseph were to publicly proclaim that he was not the father of the child in her womb.
“But as he considered these things (Mary’s pregnancy), behold, an angel of the Lord appeared to him in a dream, saying, ‘Joseph, son of David, do not fear to take Mary as your wife, for that which is conceived in her is from the Holy Spirit. She will bear a son, and you shall call his name Jesus, for he will save his people from their sins.’”
This miraculous virgin birth of a savior would prove to be a pivotal turning point in the history of mankind. Joseph, would forever be known as a man who listened to God and was faithful to both his wife and the law.
“All this took place to fulfill what the Lord had spoken by the prophet: ‘Behold, the virgin shall conceive and bear a son, and they shall call his name Immanuel’ (which means, God with us). When Joseph woke from sleep, he did as the angel of the Lord commanded him: he took his wife, but knew her not until she had given birth to a son. And he called his name Jesus.”