Gospel: Mt 1:18-24. This is how Jesus Christ came to be born. His mother Mary was betrothed to Joseph.
Her husband Joseph, being a man of honour and wanting to spare her publicity, decided to divorce her informally. He had made up his mind to do this when the angel of the Lord appeared to him in a dream and said, 'Joseph son of David, do not be afraid to take Mary home as your wife, because she has conceived what is in her by the Holy Spirit.
She will give birth to a son and you must name him Jesus, because he is the one who is to save his people from their sins.'
Now all this took place to fulfil the words spoken by the Lord through the prophet: The virgin will conceive and give birth to a son and they will call him Emmanuel, a name which means 'God-is-with-us'. When Joseph woke up he did what the angel of the Lord had told him to do: he took his wife to his home. (Jerusalem Bible – 1966)