How on earth does 'the commandment' produce and 'opportunity' for Sin?

The identity of the man described in Romans 7:7-25 has been the subject of considerable discussion in scholarly circles. I tend to agree with the growing majority that it does not refer to Paul post-conversion, but must refer to either him or Israel without Christ. However this observation has never made it easy for me to really understand how on earth, 'the commandment [not to covet], produced in me all kinds of covetousness' (v.8). It on the face of it makes no sense and obviously Paul is well aware of that and explains how this counter-intuitive sequence of events occurs because of Sin (n.b. capital 'S'). However, I have never been able to get behind this explanation to understand more clearly what is going on [this has often made me wonder whether I am just a little dim]. This is also why I’ve never really been able to understand when Tom Wright commenting on this passage says things like:

Torah could not of itself condemn sin in the flesh in such a way that it (sin) was fully dealt with. It could only heap up sin in the one place.

I have serious problems comprehending how sin can be heaped up. This is probably why I have had problems when Alistair Roberts adds that

it is important that we notice that this aspect of Christ’s death focuses on His dying for the sins of the covenant people of Israel. Christ dies for the nation first and foremost (e.g. John 11:50; Galatians 3:10-14; Hebrews 9:15). He dies by extension for the sins of the whole world (1 John 2:2).

As you can see it is not as if this is an unimportant problem concerning just this one passage either, it affects how you do biblical theology, and how you understand Christ’s death too. In the light of this two different people have been very helpful in helping me to get it together a bit more.

Alistair Roberts (again) recently wrote that:

The Ten Commandments were primarily intended to teach people how to live in God’s presence. Unfortunately, Sin starts to grow in power as it comes into the presence of God. Outside of the presence of God Sin is like a slumbering dragon. When God comes close Sin awakes and starts to rebel. Those who are brought into the presence of God will find that their struggle with Sin becomes more and more intense. This is one of the ways in which God’s Law increases the power of Sin.

This passage only jumped out at me because I had recently read Lesslie Newbigin saying:

As the coming of Jesus precipitated a crisis for Israel, so the coming of the Church will precipitate a crisis for the world. The coming of light into darkness must necessarily have this effect. In the darkness things can be hidden; when the light comes people have to choose. If Jesus was rejected, so will his mesengers. Not only so, there will be false Christs. The coming into the world of the promise of total salvation, of a radically new age, precipitates at the same time the appearing of those who offer salvation on other terms.

(The Gospel in a Pluralist Society, p. 122, London: SPCK)

At risk of moving on to the personal without enough emphasis being paid to the corporate, you can easily understand how Romans 7 has so often been related to the Christian’s experience in the history of interpretation. We still face the battle against the old self rebelling against the presence of God as Israel did corporately and individualy. However I doubt Paul would describe the battle for the Christian as Sin vs. ‘the commandment’. Now it is the battle between Sin and the heavenly (and future) reality in Christ mediated by the Spirit. This time the result will be very different BUT ONLY BECAUSE the previous battle was fought in Israel and, after the rout, defeated by Israel’s champion: the king of the Jews.