Please read the passage before the commentary.
Who was King Ahaz? He was the ninth King of the southern kingdom of Judah after King David. He lived at a time when war was threatening to destroy his kingdom. He wanted to have a powerful neighboring pagan kingdom to help him in the conflict. He was not asking the Lord for a sign because he did not believe in the Lord.
Isaiah went to king to persuade him to rely on the Lord his God. Even though Ahaz said he did not believe in God, Isaiah ended by promising a sign from the Lord.
It was the sign of a royal birth. Was it that the King would have a son and heir? Was it that human generations would continue? Was it eventually that Mary would conceive the Christ?
Virgin: The Hebrew Word, alma, used here, means simply a young woman of marriageable age. It is less specifiic than virgin is in English. IN Lthe book of Leviticus, it speaks of a virgin not married so vierginmcouldm alsomean a Young woman married. It could refer the the king’s pregnant queen. It could refer to young women in general whose marriages would continue to populate the earth.
The oldest Greek tranlation of the Bible, the Septuagint, translated the Hebrew Word as virgin. The Vulgate of St Jerome also translated it as virgin.
The child referred to may be the next King. It could mean a leader who would save the kingdom of Judah from its present danger in Ahaz’s time. Although Isaiah would not have known this, the promise of a child would be completely fulfilled in the birth of Jesus Christ, who is Emmanuel, God-with-us.