Sickness is the consequence of sin. The fall of man in the Garden of Eden brought all human race under sin, Satan and condemnation as a result of man’s disobedience to God. The whole creation was brought under the curse and all men (in Adam) became sinners and captives to sin, Satan and sickness. (Romans 5:12)
God undertook the redemption of man by sending His only begotten Son, Jesus Christ to die in man’s place to redeem man from the consequence of sin and the captivity of Satan to enjoy healing and health through the redemption that is in Christ Jesus. (Roman 3:23-26; Galatians 3:13, 14, 4:3-5; Ephesians 1:7; Colossians 1:13, 14; Hebrew 9:12-15; 1 Peter 1:18, 19)
Healing of sickness and disease as well as continued health are provided for all men through the sacrificial death of Jesus Christ. In the Old Testament, there was a divine plan by which God healed all those who were in covenant relationship with Him through the new birth.
It is not everyone that can enjoy this unfailing healing and health plan made by God for all mankind based on the fact that not all men are in covenant relationship with Him. The promise to keep the Israelites from diseases by which the Egyptians were afflicted was made at the instance of the healing covenant Israel made with God. (Exodus 15:26; Deuteronomy 7:15; Psalm 103:1-5) Diverse sicknesses, pestilences and plagues came upon them when they disobeyed God and broke His covenant. (Deuteronomy 28:28-61; Psalm 107:17-20) but when they repented and prayed, fulfilling the covenant conditions, they were healed (Numbers 21:4-9; 2 Chronicles 7:13, 14; Psalm 107:17-20)
Divine healing and health, like salvation, has remained the right of every child of God. It is a vital part of complete salvation. Sickness, in whatever form, is of the devil. God calls it captivity. (Job 42:10), Jesus called it bondage (Luke 13:16, 12) and the Holy Spirit calls it oppression (Acts 10:38).
The victory of Jesus is our victory. He did nothing for Himself. He conquered sin, Satan, disease and sickness on our behalf. He bore our infirmities, sicknesses and diseases so that we could claim full release and deliverance. But disobedience to God’s word, misuse of tongue and unbelief will make the covenant of no effect. For the people of God, no more can anyone enjoy the blessing of healing without current relationship with God through Christ, obedience to the word of God and fulfilling the terms and conditions of healing. (Exodus 15:26, 23:25, 26; Deuteronomy 7:12-15, 6-9; Psalm 91; Isaiah 1:19; Mark 2:5, 9, 11; 3 John 2)
Most often infirmities comes as a consequence of disobeying God (Genesis 20:1-18; 1 Chronicles 10:13), through Satan, the very source of sickness and affliction (Job 2:6,7; Matthew 4:23, 24; John 10:10, 8:44, 5:14; Acts 10:38), backsliding (2 Chronicles 16:12-14; Matthew 12:43-45), misuse of the tongue (Numbers 21:4-6, 11:1-3, 12:1-10), sin, covetousness of merchandising God’s gift (2 Kings 5:20-27), rebellion (Psalm 107:17-20; Deuteronomy 32:39-41) or even breaking God’s law of nature.
The scripture reveals that evil spirits, devils and demons also assist Satan in his destructive work on human bodies. They possess, oppress, afflict, torment, obsess people and cause dumbness and deafness (Matthew 9:32, 33; Mark 9:25-27), blindness (Matthew 12:22), grievous vexation and torments (Matthew 15:22), lunacy (Matthew 4:24; Luke 9:38-42) and suicide (Matthew 17:15).
Satan and his cohorts gain entrance into man when he sins, consult with familiar spirits, practices palm reading, magic, witchcraft, fortune telling, not guarding the mind or refusal to resist the devil.
Be born again, Renounce and denounce the works of the devil for total emancipation from his claws. (Matthew 13:15)
From Bible Doctrines by DCLM