There is no good thing in the flesh. After all the Lord did to crucify the affect of sin in our lives by taking it in his own body on the cross, we ought not then put our hope, trust or confidence in the thing whose power he stripped. The thing that has no life, nor gives any life. The flesh is only the servant of sin. As believers, our only relationship with the flesh should be to (spiritually) crucify it as our Lord did.