The first principle of sound demonology is that you cannot have a more adequate idea of Satan than you have of God. That is because Satan is God's creature, and creatures must be understood in relation to their Creator.
Today's Western world, having lost the knowledge of God, is currently in process of losing the knowledge of man and of Satan. Man is thought of as no more than a sort of ape, Satan is seen as no more than a medieval bugaboo (i.e., a sick fancy), and temptation is reduced to conflict between our higher and lower natures (Freud's ego and id). We need biblical clarity, and we must start with getting our minds straight about God himself.
How, biblically, should we think of God's omnipresence? The word means that God knows exhaustively, and upholds and touches continually, every single item in the universe he has made, from the tiniest genes and electrons to the most massive stars in the expanding universe to the most complex mind-body interactions in the psyche of over 6 billion people. God is here, there, and everywhere, and his mind and hand are on everything. We are never out of his sight (Psalm 139), and we cannot get away from him (John 1). Wherever we are, he is there too. This is not simply a matter of transcending spatial confines. Strictly speaking, God has no spatial location at all, for space belongs to the created order and exists in him rather than he in it. Such is the omnipresence of God.
What to think, then, of "your enemy, the devil" (1 Peter 5:8)? "Devil" means slanderer, through malice and misrepresentation; "Satan" means adversary. He is called the evil one and an enemy (Matthew 13:19), a murderer and the father of lies (John 8:44), who "has been sinning from the beginning" (1 John 3:8). He is ...