James 1:17:

Every good gift and every perfect gift is from above, and cometh down from the Father of lights, with whom is no variableness, neither shadow of turning.

Notes on James 1:17:

This is a New Testament confirmation of Malachi 3:6.

God gives you good and perfect things.  If something isn’t good and perfect, it didn’t come from God.  Sickness is not good and it is not perfect, therefore it is not from God.

See also:

Notes on Malachi 3:6
Notes on Exodus 15:25-26
Jesus the Healer Has Never Changed
Healing – a Gift from God
Healing Is a Good Thing
Would You Rebuke a Christmas Present?
You Have Faith
Objection: Healing and Miracles Are Not for This Current Dispensation
Objection: God’s Healing Covenant in the Law of Moses Was Only for the Jews
Objection: God Gives and Takes Away
Objection: We Cannot Demand Healing from God Because God Is Sovereign
Objection: If God Wanted Us to Enjoy Perfect Health NOW, He Would Have Already Given Us Immortal Bodies
Objection: Terminal Illness Can Be a Gift from God
Objection: Mental Illness Is Treatable But Not Curable
Objection: Sometimes God Says, “Yes,” Sometimes He Says “No,” and Sometimes He Says, “Wait” When You Ask for Healing
Objection: God Does Great Miracles Only During Crucial Times in History
Objection: Like Any Loving Parent, God Sometimes Has to Tell His Children NO for Their Own Good