Lucifer thought of himself as the son of the morning- How art thou fallen from heaven, O Lucifer, son of the morning! Isaiah 14:12.
He thought he should be like unto God Himself...I will ascend above the heights of the clouds; I will be like the most High. Isaiah 14:14.
But who is truly the star of the morning?-I Jesus have sent mine angel to testify unto you these things in the churches. I am the root and the offspring of David, and the bright and morning star. Revelation 22:16
Lucifer tries to counterfeit everything God does. Including a counterfeit to the Holy Sabbath Day by implementing Sunday in its place.