18 Now the birth of Jesus was like this: His mother Mary was engaged to Joseph; before they were married (came together) it was discovered that she was pregnant by means of the Holy Spirit.
19 Now Joseph, her husband, was a just man and did not want to expose her publicly, so he decided to divorce her privately.
The events that Matthew records concerning the birth of Jesus are not to be found in any of the other gospels. Therefore, he must have learnt about these circumstances from another source.
We know that Matthew was one of the twelve disciples of Jesus. It is highly probable that he would have known Mary, the mother of Jesus. In view of this it is also probable that his information could have come from Mary.
Luke records different things concerning the conception and birth of Jesus, but he agrees with Matthew that His conception was not by human means:
34 Mary said to the angel: “How can this happen, since I don’t know a man?”
35 The angel answered her: “The Holy Spirit will descend (and operate in you) upon you and the power of the most high will envelope you. Therefore, the one being born will be called: Son of God” – Luke 1.34-35.
Verse 18 begins with the word : ‘now’ or ‘but’, which suggest that what follows is different to what has preceded. Matthew has given the family lineage of Joseph going back as far as Abraham (Luke traces the family line back to Adam – chapter 4.23ff. As we have seen there are some variations in the two accounts.)
Up to this point Matthew has followed the same pattern: Abraham was the father of etc.
This changes in verse 18 with the introduction of the word: ‘but’ or ‘now’. The conception and birth of Jesus was different, in that such an event had never been known or heard of before.
From this we can see that both Matthew and Luke are agreed that the conception of Jesus was by the Holy Spirit.
The same is true for us becoming the sons of God:
12 But as many as received Him, to those believing in His name, He gave to them the right to become the children of God,
13 who were not born of blood, neither from the will of human nature, neither of the will of a husband, but from God – John. 1.12-13.
We are born again of the Holy Spirit.