I had to laugh when I read the Isaiah passage, where God urges King Ahaz to ask for a sign, as “deep as Sheol or high as Heaven.” God wants to get His point across. But Ahaz answers, seemingly pious and faithful, “I will not put the Lord to the test.” Now here’s the funny part, when Isaiah says, “Is it too little for you to weary mortals, that you weary my God also?” then lays on Ahaz the sign he didn’t ask for.
Fast forward to the Matthew passage. Joseph learns that his intended bride is pregnant. Imagine his thoughts. Things are NOT going according to plan! Who could blame him if he got angry and lashed out? But no, he is a righteous man and doesn’t want to disgrace Mary.
Then Joseph has a dream. An angel reminds him of the sign given to Ahaz 700 years earlier, “Look, the virgin shall conceive and bear a son, and they shall name him Emmanuel.” The prophesy will be fulfilled in Mary and her son will be “God is with us.”
This must have been hard to understand and hard to believe. But Joseph knew this was a BIG deal, and he accepted it.