Spiritual struggle is a continual, effortful war against the pulls of the flesh and against Satan, and it is the means by which God matures character. Jesus, Paul, James, and Peter insist that struggle is vital to conversion and growth, and Jesus says the violent, those who strive fiercely, take the kingdom by force (Matthew 11:12). Paul describes the life-and-death conflict of the law in his members warring against the law of his mind (Romans 7:23). God does not tempt anyone; temptation comes from our own desires, which Satan the Tempter amplifies by exploiting appetites such as hunger, thirst, sleep, and sex. God deliberately subjected humanity to this condition in hope, knowing that continuous struggle against corruption would perfect the character needed for His Family. Resisting temptation works like lifting weights: repeated resistance builds the strength of the inner man over time. Man needs not a tensionless state but striving toward a worthy goal. Because man is a free moral agent, God wants obedience chosen without coercion, and He gives His Spirit to those who desire it and obey. Fasting is a vigorous exercise in this fight. It tears down enslaving habits, brings us face to face with our carnality, and forces us to cry out to God, who promises strength and a way of escape (I Corinthians 10:13). We submit to God and resist the devil (James 4:7-8), and God replaces the torn-down pulls with fresh measures of His Spirit, which builds holy character. Jesus' 40-day fast against Satan is the model, and some spirits depart only by prayer and fasting.

The ongoing struggle between the Spirit and the flesh in every believer is not double-mindedness. Paul's anguished complaint in Romans 7:19 describes a mind focused in one direction (verse 22) while the flesh carries an innate enmity toward God and His law (Romans 7:23; 8:7). Like Paul, all fail to keep God's law perfectly because human nature is perpetually at war with God's Holy Spirit within. Mind-wandering in prayer, indecision, and ordinary doubts and fears are undesirable and should be rooted out, but they are symptoms of this struggle, not the double-mindedness James condemns. The father in Mark 9:24 who cried, "Lord, I believe; help my unbelief!" was not double-minded, because he wanted to believe and asked for help. Everyone has a deep desire to be at one with himself, but this wholeness will not come until we are composed totally of spirit. Until then, a spiritual tug of war continues. As God's Spirit renews the mind and displaces carnality, the carnal nature becomes easier to keep in check, and areas once out of control come under control. Double-mindedness is different: it is knowing God's law and deliberately harboring a sin, then concealing or excusing it, as Saul did with the Amalekites. It produces cognitive dissonance and cannot coexist with God's Spirit. The believer must choose God's side in the battle between spirit and flesh, and yielding to God's law through Christ's power brings wholeness and singleness of purpose.

After baptism the Christian faces a continuous fight against the world, the flesh, and the devil, and the flesh is the most formidable opponent because the carnal mind is enmity against God and must be crucified, mortified, and slain utterly, like a soldier ordered to take no prisoners. The war is not against people but against one's own nature. Israel's conquest of the Promised Land is the pattern. God's promises in Exodus 23 to drive out the inhabitants are conditional on obedience and cooperative: "I will drive them out" ends with "YOU shall drive them out." Israel knew from the census of fighting men and the warning against covenants that war was coming. The people of the land symbolize human nature, which cannot be overcome without God, though God makes the fight far easier than it would be alone. God does not make growth easy, since nothing would then remain to overcome and His law would not be written in the heart through practice. He tests to humble us and reveal where we stand, and He never allows a test beyond what we can bear (I Corinthians 10:13). Obedience costs sacrifice, and fear of that cost drives us to compromise. Israel drew back in fear at Kadesh, which was rebellion and a failure of faith, and that generation died in the wilderness. Christ, though innocent, suffered most, so growth brings harder tests, like advancing through school. We will not win every battle, but God is patient, never leaves nor forsakes us, and brings us back to fight again until we overcome.