In Matthew chapter one we read of Joseph's plan to divorce Mary quietly when he discovers she's pregnant before they've been married. An angel appears to Joseph and tells him not to be afraid to take Mary as his wife because her son has been conceived by the power of the Holy Spirit. Moreover he is to name the child "Jesus" (rough Greek transliteration of the Hebrew Y'shua, "Yahweh saves") because he will save his people from their sins. Matthew then reminds us of the prophecy of Isaiah that the virgin will conceive and bear a son and his name will be called "Immanuel, meaning God with us."
These two names, Jesus and Immanuel, summarize the plan of God for salvation. Yahweh will deliver his people. Everyone who calls upon the name of the Lord will be saved. As He once carried the children of Israel up from their bondage in Egypt, so once more, God would reach down and save not only the family of Jacob, but would bless all the families of the earth by freeing them from their greater bondage to death and sin. And He would do it by coming among us. He would live the life of a man. He would suffer and be tempted as we are. He would take up into himself our broken, corrupted flesh. He would die our death accursed and forsaken and so pay the price of our sin. Then in that same frail, dead, human flesh He would rise again transformed and renewed, made perfect in obedience. He would receive from His Father the name that is above all names and be proclaimed in power as the one and only Eternal Son of God. In that death and resurrection and ascension and sitting at the right hand of the Father, He too would raise all those who by faith are found in Him to a new and indestructible life eternal.
Immanuel, God himself with us, was Jesus, the sign of salvation and deliverance for all.
For God so loved the world that He gave His one and only son, that whoever believes in Him should not perish but have everlasting life.
O come let us adore Him, Christ the Lord!