“And she shall bring forth a son, and thou shalt call his name JESUS: for he shall save his people from their sins.”
Matthew 1:21 — Greek Interlinear
Church Fathers on Matthew 1:21
What the Angel thus told Joseph, was beyond human thought, and the law of nature, therefore he confirms his speech not only be revealing to him what was past, but also what was to come; 'She shall bring forth a Son.'
That Joseph should not suppose that he was no longer needed in this wedlock, seeing the conception had taken place without his intervention, the Angel declares to him, that though there had been no need of him in the conception, yet there was need of his guardianship; for the Virgin should bear a Son, and then he would be necessary both to the Mother and her Son; to the Mother to screen her from disgrace, to the Son to bring Him up and to circumcise Him. The circumcision is…
He said not, 'Shall bear thee a Son,' as to Zacharias, 'Behold, Elisabeth thy wife shall bear thee a son.' For the woman who conceives of her husband, bears the son to her husband, because he is more of him than of herself; but she who had not conceived of man, did not bear the Son to her husband, but to herself.