Why is there spiritual warfare in a believer?
Spiritual warfare exists because the indwelling Holy Spirit empowers the believer’s spirit to stand against old Adam and Satan. Old Adam is crucified and defeated in God’s sight yet still present and powerful in experience. This conflict would not exist—and there would be no battle line—without the indwelling Holy Spirit.
Les explains that once old Adam is crucified, in God’s eyes he is completely dead and out of the picture, yet in the believer’s experience he is still here. Old Adam is defeated and does not have to remain uppermost; if he does, it is because the believer is not fighting the battle. The Holy Spirit came in and empowered the believer’s spirit—body, soul, and spirit—so that the Spirit working in consort with our spirit enables victorious living. Old Adam is powerful and will come to the fore at times, and that is where the warfare exists. There would be no warfare or battle line were it not for the indwelling Holy Spirit; without Him, the believer would not stand a chance against the forces of old Adam and Satan. Les ties this to the Greek Pneuma Hagion, meaning power from on high.