ISB ~ Matthew 1 v18

betrothed to Joseph:Betrothal in ancient Judaism was unlike modern-day engagements. It was a temporary period (up to one year) between the covenant of marriage itself and the time when spouses lived together. Because couples were legally married during this intervening phase, a betrothal could be terminated only by death or divorce (Deut 24:1-4).

of the Holy Spirit:Often read as an editorial comment addressed to the reader. Others take it to mean that Joseph himself had come to learn that Mary’s pregnancy was the result of a miracle.