In reading this I couldn't help but notice Joseph's perspective of his motive in contrast to the angel's perspective.
"Now the birth of Jesus Christ took place in this way. When his mother Mary had been betrothed to Joseph, before they came together she was found to be with child from the Holy Spirit. And her husband Joseph, being a just man and unwilling to put her to shame, resolved to divorce her quietly. But as he considered these things, 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.' All this took place to fulfill what the Lord had spoken by the prophet:" - Matthew 1:18-22 ESV
The angel communicated that fear was at the root of Joseph's thoughts of purposeful abandonment. Joseph was about to make a fear based decision. The child clearly wasn't 'his' child but the child would save 'his people.'
Joseph was just and his fear was hidden behind good intentions. That is a danger associated with being a moral good person. Decisions can get a layer of justification.
The angel dared Joseph to switch to a redemptive mindset.
I think God wants us to make that shift in areas today. We must move from what is good in our own eyes to what is redemptive in God's eyes in order to see 'prophetic' fulfilment on a personal level.