About the revealing of God's light:

Matthew 2: 16 When Herod realized that he had been outwitted by the Magi, he was furious, and he gave orders to kill all the boys in Bethlehem and its vicinity who were two years old and under, in accordance with the time he had learned from the Magi. 17 Then what was said through the prophet Jeremiah was fulfilled: 18 "A voice is heard in Ramah, weeping and great mourning, Rachel weeping for her children and refusing to be comforted, because they are no more." (KJV)

Matthew 13:11 He replied, "The knowledge of the secrets of the kingdom of heaven has been given to you, but not to them.

The spiritual foundations of the world were shaken on the day Jesus was born. So shaken was the darkness in the world, King Herod slaughtered every child in Bethlehem to try and kill the light of the Christ-child. King Herod and the snakes of the darkness had reasons to panic. The darkness had reasons to panic because the Light had come into the world and against this Light no darkness could stand. In your life, no darkness can stand against the love and light of Christ. Although the world is still steeped in darkness, we have a great Light we can let shine in our heart. Although the darkness does yet attack us and try to bring us down, we have a great Light within our heart to make the darkness go away in an instant. In your heart, you may have pain but you also have a great Light to give you comfort. In your heart, you may have worry but you also have a great Light to give you contentment. The revealing of God's great Light was the Light of the world we call Christ Jesus. Because Christ came to you, you can share Him with others as you let His light shine.