Romans 5:17 says, "For if by one man's offence (Adam's) death reigned by one; much more they which receive abundance of Grace and of the gift of Righteousness shall reign in life by One, Jesus Christ."
When our children were small and the devil would try to put sickness on them, I would get mad at him and tell him to get his hands off my children. I'd say, "I'm ruling over my domain. You're not ruling this household ... I AM, through Jesus Christ!" I put him on the run ... and he ran! You can put him on the run too.
When the devil comes along and tries to steal, kill, or destroy in some way in your life ... like putting sickness on your body, just say "The Word of God says that I AM HEALED! The Word says that I live in Divine health! Now, Body, you shut up! And Satan, get out of here, in Jesus' Name!"
Romans 12:1 says that it is our responsibility to take care of the body that we live in ... this temple. God, through Jesus going to the cross, already did His part (His part is finished!)... now we must do our part. We don't always do a very good job of this and it opens the door for the devil to do his stuff to us that we don't like and don't want.
But now that we are familiar with his works, we make him flee, in Jesus' Name.
Reverend Robert W. & Mary C. Butler