When the prophet was given these words to speak to the Jews, many of them had become idolatrous. So God says to them that He alone is God not the idols and He alone can blot out their sins if they come to Him.
There is an alarming increase of people claiming to love Jesus while at the very same time blatantly and unashamedly practicing sin. Have these no fear of hell, of God’s wrath? This is a leaven in the churches.
The coming of Jesus Christ is far more glorious than any birth before or after. His glorious entry and subsequent life, death and resurrection was for everyone, for the world. There is nothing more glorious or needed for saving sinners.