In the natural realm, we derive sickness from causes such as: genetics, bacteria, viruses, violating natural laws, poor lifestyle choices (i.e., diet), external trauma, stress, and psychosomatic illness as a result of emotional issues manifesting themselves physically.

In the spiritual realm, you should understand that sickness comes from satan (e.g., Job 2:7). This cannot be left up to interpretation or viewed on a case-by-case analysis. In order to overcome sickness, it is important that you know where sickness originates in order to resist it successfully. In order to resist illness, you must submit to God. The act of submission and resistance are your responsibility.

It is also imperative to know satan is aware that God’s resistance is relative to your resistance. God wants you to live a healthy life; but as a free moral agent, you must want the same for your life. As you fight sickness in the natural and spiritual realms, it is paramount to embrace these three (3) truths about sickness:

01 Sickness was NEVER part of God’s plan for you

        Romans 5:12 - Therefore, just as sin entered the world through one man, and death through sin, and in this way death came to all people, because all sinned—

02 Sickness is a work of satan

        Acts 10:38 - How God anointed Jesus of Nazareth with the Holy Ghost and with power: who went about doing good, and healing all that were oppressed of the devil; for God was with him.

03 Sickness is an EVIL thing

        Deuteronomy 7:15 - And the Lord will take away from thee all sickness, and will put none of the evil diseases of Egypt, which thou knowest, upon thee; but will lay them upon all them that hate thee.

        Since sickness comes from the devil and described in God’s Word as evil, we must understand that nothing good can come from sickness; it is the not-so-distant cousin of death, while life is connected to good. It is impossible to extract good (healing) from evil (sickness).

Resource:

Sickness: An Enemy of God’s Plan for Man Vol. 1-4