The angel of the Lord— Probably Gabriel, who had been sent to Zecharias and Mary. That Joseph's scruple did not proceed, as some of the fathers suppose, merely from veneration, appears from the reason given why he should take Mary, which in that case would have been the only reason against it. Some read the next clause, Scruple not the taking of Mary thy wife. The last phrase, is of the Holy Ghost, means, "Hath been formed by the Holy Ghost." See Psalms 118:23. It is observable, that the angel reminds Joseph of his descent from David, as it were to awaken his hopes, and to raise his thoughts to the great event which was now about to open to his view.
Related Commentaries of Matthew 1:20
Matthew 1:20
20 But while he thought on these things, behold, the angel of the Lord appeared unto him in a dream, saying, Joseph, thou son of David, fear not to take unto thee Mary thy wife: for that which is conceivedb in her is of the Holy Ghost.