On the 'wretched man that I am' passage, my take on this one is that many Christians find themselves in this kind of dilemma, bec ause they have never learned/ been taught to distinguish between spiritual realities (dead to sin, new creations in Christ) and the carnal nature (physical urges, emotional habits, ingrained thought-patterns), from which we are potentially free - when we focus on the reality of what Christ has done for us - but which we are often tempted to make undue provision for. We are to see these things as 'dead', therefore having no claim over us, for, if we do not, then it is easy to find excuses why living the Christian life is 'too hard', 'not fair' etc.. The truth is, our bodies and minds don't enjoy being trained in a new way of living - but as 'dead men' they have no right to dictate to us what we do. This is, indeed, what 'sanctification' is all about - making our bodies true temples of the Holy Spirit, in the practicalities of day-to-day living, as well as in abstract theological terms. Christ 'delivered us from the body of sin' ince for all upon the cross, which we appropriated by faith when we made him our Saviour and Lord. Yet the ongoing application of that reality is an ongoing, daily decision - will we live as the sons and daughters of the Living God that Christ has made us to be, or as the children of this world, which comes so much more 'naturally' to us, even tho' it is no longer the 'true us'?
Anthony