Although he has persuaded many people that he doesn't even exist, Satan very definitely is a real, personal being, the fountainhead of all unbelief and of every kind of moral and spiritual evil in the world. He is called by various names in the Bible, including Satan (meaning, “adversary”—Job 1:6; Romans 16:20; etc.), the devil (i.e., “slanderer”—Matthew 4:1; 1 Peter 5:8; etc.), Lucifer (Isaiah 14:12), the serpent (2 Corinthians 11:3; Revelation 12:9; etc.), and many others.
To the Christian, the existence of Satan as a real person is proved by the fact that the Lord Jesus Christ recognized him as such. He referred to him frequently by name (e.g., Luke 10:18; Matthew 4:10; etc.) and indeed called him “the prince of this world” (John 12:31; 14:30; 16:11).
The Apostle Paul called him the “god of this world” (2 Corinthians 4:4) and the “prince of the power of the air” (Ephesians 2:2). The Apostle John said, “The whole world is under the control of the evil one” (1 John 5:19) and that he is the one “that leads the whole world astray” (Revelation 12:9). These could hardly be the descriptions of a force or a mere personification of evil.
The Scriptures teach that, before man and the world were created, God had created an “innumerable company of angels” (Hebrews 12:22), a heavenly host of spiritual beings, of great strength and intelligence. The highest of these beings are the cherubim, who are attendants at the very throne of God, and the “anointed cherub” at that throne was originally Satan himself (Ezekiel 28:14). He was “full of wisdom and perfect in beauty.”
God did not create Satan as an evil being, however. The angels, like man, were created as free spirits, not as unthinking machines. They were fully able to reject God’s will and rebel against His authority if they should chose to do so.
The root of all sin, in both man and angels, is the twin sin of unbelief and pride—the refusal to submit to God’s will as revealed by His own Word and the accompanying assertion of self-sufficiency which enthrones the creature and his own will in the place of God. This was the original sin of Satan, rejecting God’s Word and trying to become God himself. He said in his heart, “I will ascend into heaven, I will exalt my throne above the stars of God . . . I will be like the most High” (Isaiah 14:13,14). Again, these could hardly be the actions or motivations of an impersonal force.
Jesus also told us of some of the characteristics of Satan. Christ said he was a murderer from the beginning, not holding to the truth, for there is no truth in him, and that when he speaks he lies, he speaks his native language, for he is a liar and the father of lies (John 8:44).
It is crucial that Christians recognize the reality of Satan in this world and understand that he prowls around like a roaring lion looking for someone to devour (1 Peter 5:8). It is impossible to overcome sin and temptation from the devil by ourselves, but Scripture tells us how be strong. We need to put on the full armor of God daily to be able to stand our ground against temptation (Ephesians 6:13) from the very personal being, Satan.