A number of times during His earthly ministry our Lord cast out demons from various people. These instances, of course, affirmed His belief in their real existence (Matt. 12:22–29; 15:22–28; 17:14–20; Mark 5:1–16). He also gave the disciples authority to cast out demons in a context that did not require, as some allege, accommodation to their ignorant belief in demons (Matt. 10:1). Never did our Lord correct anyone for their acceptance of the reality of demons (Luke 10:17), yet He was willing on many other points to correct false theology.
If we cannot accept the Lord’s testimony, then we would have to conclude that either (a) He was lying, or (b) He was accommodating His teaching to the ignorances of His audience (which in effect makes Him guilty of propagating falsehood), or (c) the early church redactors of the text added the parts about His teachings on demons.
Ryrie, Charles Caldwell. 1999. Basic Theology: A Popular Systematic Guide to Understanding Biblical Truth. Chicago, IL: Moody Press.
Demons are real spiritual beings mentioned throughout the Bible. They seek to deceive, harm, and lead people away from the truth of Christ. Scripture warns that they influence the world through lies, temptation, and oppression, but they are powerless against the authority of Jesus. Believers are called to resist them through faith, prayer, and the Word of God, knowing that Christ has already won the victory over all evil (Ephesians 6:12, James 4:7).
-Elving Ellis
Cross Commission Ministries 