The cross is our greatest weapon. Through what Jesus did on the cross, we have freedom, forgiveness, peace, victory, restoration and most importantly, a relationship with God. Just think of it, if Jesus had not have gone to the cross, we would be far from God; It is through Jesus that we have been brought close to God!
Not only did Jesus die for our sins on the cross, but he died for our sicknesses, worries, burdens and everything that holds us in bondage. So now, because of what Jesus has done, we no longer need to suffer from disease any more because on the cross he said it is finished, so we don't have to experience something Jesus has already conquered. I encourage you, to keep praying that any diseases or sicknesses would leave you, because remember you don't have to live with them. When Jesus said it is finished, I believe he literally meant all sin, all death, all disease had been defeated there and then.
If we accept this as true, and don't believe otherwise, we will see the power of God transform our lives, for the truth is that Jesus has done all the hard work, we just have to accept that and choose to follow him.
Another thing we have through the cross is victory, victory over our enemy the devil. So whatever attack or trick he throws at you, whether it be condemnation, accusation or anything else, through the cross you have the victory over him, for that is where he truly lost.
May God be with you, and may he show you the power in his name through the cross!