Joseph has a dream.
I don’t know about you, but I’ve got some issues with believing a dream! I view my dreams with great suspicion, always considering them as NOT prophetic.
In Joseph’s case, his betrothed is visited by Gabriel, whose words to her confirm Joseph’s dream. (Luke 1: 26 – 33)
Where two are gathered in [His] Name, there He is also. (Matthew 18: 20)
Gabriel, who is the angel of the Lord, refers to the prophet Isaiah, who writes: “Behold, the virgin will conceive and bear a son, and they shall call His Name Immanuel.” (Matthew 1: 23)
Gabriel tells Joseph to name his son Jesus, “for He will save His people from their sins.” (Matthew 1: 21)
Like Mary before him, Joseph believes. I do think he confirms this dream with Mary, speaking with her later, hearing her report of Gabriel’s visit and the angel’s words to her. Gabriel’s visit to Mary comes before she “is found to be with child from the Holy Spirit.” (Matthew 1: 18) Gabriel tells her beforehand not to be afraid, that the Holy Spirit will come upon her, overshadow her and give her the baby who is Jesus. She keeps this to herself, sharing it later with Elizabeth. I see her not sharing it with Joseph, perhaps out of fear. After all, she knows she may be stoned to death, outside the city gate. But when Joseph finds Mary pregnant, he is just and decides “to divorce her quietly.” (Matthew 1: 19) He is kind and does not want Mary to die. Perhaps he also does not want her unborn child to die.
When Gabriel tells Joseph to take Mary to be his wife, Joseph confirms the dream with Mary. All that Mary has stored in her heart now comes out. I imagine her relief and her thrill to find that Joseph is also a faithful servant of God; that he also is willing to obey.