Because we live on this side of Christmas, we want to rush to the end of the story where everything turns out okay. We miss the anxiety in a young woman's announcement, "I'm pregnant" and the tension on a man's brow as he parses the right decision. You might even be tempted to think Joseph was slow spiritually and should have figured out what was going on a lot sooner. But if you do that, you miss the whole point of what Joseph is learning, and of what we can learn from him—that there's some amazing stuff going on around Christmas besides how Jesus got here. You miss out on how God is already beginning to redefine what true righteousness is.
Matthew 1:1819 tells us: "This is how the birth of Jesus Christ came about: His mother Mary was pledged to be married to Joseph, but before they came together, she was found to be with child through the Holy Spirit. Because Joseph her husband was a righteous man and did not want to expose her to public disgrace, he had in mind to divorce her quietly."
Joseph, Scripture says, was a righteous man. There's a rich history behind this idea. The Hebrew word for a righteous man is tsaddîyq. Joseph was a tsaddîyq, and this means he was known for his uncompromising obedience to the Torah, the law of Moses. (For some of this concept I'm indebted to an article by Scott McKnight, a New Testament scholar.)
Joseph didn't eat unclean food. He didn't mix with the wrong kinds of people. He didn't keep his carpentry shop open on the Sabbath to make a few extra drachmas. He was a tsaddîyq; that was his identity. Everybody knew this about him. Nobody invited Joseph over to have ham sandwiches with tax collectors and prostitutes. He was what people wanted to be. Like a businessman in our day wants to be a CEO, or like an athlete wants to be an all-star, an Israelite wanted to be a tsaddîyq. Becoming one meant you were admired and looked up to. Then you were somebody. And that was Joseph.
But now he's a tsaddîyq with a problem. The girl he has promised to marry is going to have a baby, and whoever the father is, Joseph knows it's not him. Nazareth is a small town, and as a general rule, word gets around in a small town. So we have a tsaddîyq and a pregnant fiancé;e in a small village where, as a general rule, everybody knows everybody's business.
The Torah has some clear instructions about what to do to somebody in Mary's condition. A section in Deuteronomy 22 covers marriage violation. If a woman pledged to be married is unfaithful, it says: "She shall be brought to the door of her father's house, and there the men of her town shall stone her to death. She has done a disgraceful thing in Israel by being promiscuous while still in her father's house. You must purge this evil from among you."
The Torah was clear. Joseph's reputation as a tsaddîyq was on the line. His fellow tsaddîyqim would have told him this sin must be publicly exposed and punished. But Joseph couldn't bring himself to do this.
The Ministry of Disequilibrium
Being a righteous man, Joseph must have agonized over this day after day. When the angel comes to him, Joseph already knows Mary is pregnant. How did he find out? Mary would have told him. Put yourself in his place. Your fiancé;e comes to you and says, "I have some bad news and some good news. The bad news is I'm pregnant even though we're not married yet. The good news is I haven't been with anybody else. An angel came to me and said, 'Hail Mary, full of grace.' I'm going to have a miracle baby, and all generations will call me blessed. I know it's never happened before, but it's going to happen."