"Take care and be quiet ; Do not be afraid, and let not your heart fail in the face of these two smoking stubs, in front of the fiery anger of Rezin and Syria, and the son of Remaliah ... The Lord will give you a sign. the virgin will conceive and she will give birth to a son, and his name will be called Emmanuel." Isaiah 7:14
Rezin king of Syria and Pekah king of Israel (the kingdom of the north) come to war against Ahaz king of Judah. In spite of God's impiety, God speaks to him through the prophet Isaiah. Divine grace and mercy characterize the words spoken to it (verses of the day). But the fear and unbelief of Ahaz prevent him from grasping the hand that God gives him. He prefers to seek help from Tiglath-Pileser, king of Assyria (2 Kings 16, 7, 8).
God speaks to him again. To assure him of the fulfillment of his promises, the Lord offers him a sign : "Ask for a sign from the Lord your God" (Isa 7:11). The king refuses (v.12) and his response manifests only deep unbelief and great hypocrisy ; he had already decided to resort to military aid from the Assyrians !
What a pity, Ahaz ! It was at this time in the history of the world that God was telling prophets like Isaiah, his thoughts and his promises, but you did not want to hear !
What a pity Ahaz ! God wanted to give you a sign : "Behold, the virgin will conceive and she will give birth to a son". It was a sign of the faithfulness of God, who from the garden of Eden had spoken of the woman's descent. But you are not of this lineage of "waiting" faith (Isaiah 18: 2) and who knows that God can do anything.
What a pity, Ahaz ! God had for you a mysterious but wonderful word : "Emmanuel", God with us, God with men ! Has anyone ever heard such a promise ? Thousands of Jewish believers hoped to hear it, but you did not have the faith to receive it. You came so close, Ahaz, and you did not see her.
But God is faithful. He will fulfill his promise despite the unbelief of the king and his people. God does not give up his plan : "If we are unfaithful, let him remain faithful, for he can not deny himself" (2 Tim 2: 13). It is not different today. I can count on his immutable loyalty.
Source (Pleasing the Lord)