Romans 7:15-25 New Revised Standard Version (NRSV)
15 I do not understand my own actions. For I do not do what I want, but I do the very thing I hate. 16 Now if I do what I do not want, I agree that the law is good. 17 But in fact it is no longer I that do it, but sin that dwells within me. 18 For I know that nothing good dwells within me, that is, in my flesh. I can will what is right, but I cannot do it. 19 For I do not do the good I want, but the evil I do not want is what I do. 20 Now if I do what I do not want, it is no longer I that do it, but sin that dwells within me.
21 So I find it to be a law that when I want to do what is good, evil lies close at hand. 22 For I delight in the law of God in my inmost self, 23 but I see in my members another law at war with the law of my mind, making me captive to the law of sin that dwells in my members. 24 Wretched man that I am! Who will rescue me from this body of death? 25 Thanks be to God through Jesus Christ our Lord!
So then, with my mind I am a slave to the law of God, but with my flesh I am a slave to the law of sin.