Matthew 1:19-23

Then Joseph her husband, being a just man, and not willing to make her a publick example, was minded to put her away privily.

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 conceived in her is of the Holy Ghost.

And she shall bring forth a son, and thou shalt call his name JESUS: for he shall save his people from their sins.

Now all this was done, that it might be fulfilled which was spoken of the Lord by the prophet, saying,

Behold, a virgin shall be with child, and shall bring forth a son, and they shall call his name Emmanuel, which being interpreted is, God with us.