When speaking of the domain of Satan and that of God’s, Scripture describes the contrast in terms of darkness and light. 

Since the time of the angelic rebellion in eternity past, to the continuing invisible warfare in the heavenlies and on earth, the struggle has intensified with mankind as its target.  It would be through the seed of the woman that would come and crush the serpent’s head.  “And I will put enmity between you and the woman, and between your offspring and hers; he will crush your head, and you will strike his heel" (Gen 3:15 NIV). 

Ever tirelessly bent on thwarting the plan of God, Satan would seek to prevent the fulfillment of that promise. Murder would be added to the satanic game plan, that of Cain killing his brother Abel (Gen 4:8). This act of violence is often misunderstood.  The thinking of Cain was in direct opposition to the revealed message of salvation given to his parents in the Garden.  Cain brought the best of his efforts as his approach to God. On the other hand, Abel sacrificed a lamb.  One offering spoke of self effort, human works in attaining God’s favor, while the other pictured that which was innocent dying for the guilty. Cain’s thinking and efforts bypassed the need of a substitute to atone for man’s sin.   Abel’s thinking was in keeping God’s plan of salvation. 

In the commendation of Abel, the writer of the Hebrews states… “By faith Abel offered God a better sacrifice than Cain did. By faith he was commended as a righteous man, when God spoke well of his offerings. And by faith he still speaks, even though he is dead” (Heb 11:4 NIV).  The Apostle John gave this warning to his readers… “Do not be like Cain, who belonged to the evil one and murdered his brother. And why did he murder him? Because his own actions were evil and his brother's were righteous” (1 John 3:12 NIV).

That evil intent was to have relationship with God based on man’s good efforts rather than faith in God’s good effort, the Cross of Jesus Christ.  As history proceeded, Israel became the focus of satanic attack.  On the eve of their exodus from Egypt, the Jews were promised…  “This evening you will know that it was the LORD who brought you out of Egypt. In the morning you will see the dazzling light of the LORD's presence” (Ex 16:6-7 TEV).  The evil of enslaving the Jews could not prevent the plan of God from progressing to bring Messiah into the world. 

Satan continued his attack against the Jews, but all his efforts failed.  Isaiah had prophesied that …“The people walking in darkness have seen a great light; on those living in the land of the shadow of death a light has dawned” (Isa 9:2 NIV).  That eighth day after the birth of Jesus, as his parents took him to the Temple, a righteous and devout man named Simeon proclaimed... “Sovereign Lord, as you have promised, you now dismiss your servant in peace.  For my eyes have seen your salvation, which you have prepared in the sight of all people, a light for revelation to the Gentiles and for glory to your people Israel” (Luke 2:29-32 NIV). 

Into Satan’s domain of darkness had come the Light of the World.  The Apostle John in his gospel would leave no doubt that this One born in Bethlehem was the Creator, God in the flesh and the Savior of mankind.  “Before the world was created, the Word already existed; he was with God, and he was the same as God. From the very beginning the Word was with God. Through him God made all things; not one thing in all creation was made without him. The Word was the source of life, and this life brought light to mankind. The light shines in the darkness, and the darkness has never put it out” (John 1:1-5 TEV).