The issues raised by the huge controversy over MPs' expenses are as grave as could be for our parliamentary democracy, and urgent action is needed to restore trust. It is good that all parties are recognising this. But many will now be wondering whether the point has not been adequately made; the continuing systematic humiliation of politicians itself threatens to carry a heavy price in terms of our ability to salvage some confidence in our democracy.

It is important to connect some of the underlying attitudes with a wider problem. In recent months, we've had a number of examples (bankers' pensions, the suspension of two peers from the Lords) of people saying when challenged that “no rules were broken”. Some of the initial responses to public anger about MPs' expenses have amounted to much the same thing. And this suggests a basic problem in our moral thinking.

The question “What can I get away with without technically breaching the regulations?” is not a good basis for any professional behaviour that has real integrity.

Integrity is about what we value in ourselves or our work for its own sake - what's worth making sacrifices for, what we're glad to have done simply for the kind of act it is. If I do something just because I'm told to, or if I hold back from something simply because of fear that I shall be caught out, it's a very different business. It has nothing to do with that sense of being glad to have done something. And without that sense, no one is really going to see public life as a vocation in the old-fashioned meaning of the word - a task you perform because you find yourself in the doing of it.

Without that sense, we always slip back towards the shabby calculation of what we can get away with. “No rules were broken”: I may have done something that is manifestly against the spirit of the rules or regulations, but technically I'm safe, even if I haven't even begun to think through from the inside what kind of person I've been making myself; what the cost is to my moral health, the person I am.

So what is it in our society that encourages this sort of myopia? We talk earnestly about the need for proper self-respect or self-esteem, yet apparently don't grasp that self-respect is just empty egotism unless it connects with that sense of being glad to do certain things because they're the kind of things they are, and because they are the way we become the kind of people we most seriously want to be. This isn't about wanting a world of smug souls regarding their behaviour with placid approval. To be glad you've done certain things is bound up with being able to see that there are also certain things you do that make you less than you could be - whether or not you get “punished” for them.

And this is why better regulation - for MP's or bankers or whoever - can't be the whole answer, important as it is. Regulation comes in, necessarily, when you recognise that you can't rely as much as you might hope on people's intelligence or goodwill. But this can turn into an excuse for failing to encourage intelligence and goodwill in the first place. Exhaustive anti-discrimination provisions, for example, get enacted when authority has found reason to suspect a comprehensive lack of charity and good sense. But they can also weaken the conviction that the best foundation for fairness is an ingrained habit of respect, bound up with one's own self-respect. And, once again, they create that disreputable atmosphere of asking how little you need to do to comply.

Religion-based morality is often castigated for imposing irrational and arbitrary rules on people. But the truth is that its primary concern is with how to encourage us to act in such a way that we can be glad of what we have done - and can also recognise that bad actions diminish us. Of course there is a debased religious morality that is all about the fear of punishment. But the major faiths all see our task as becoming what we are made to be and called to be - as growing in integrity, in fact, and responding to a vocation. God sees the heart, so there is absolutely no possibility of hiding what is really going on in us.

And this is not a threat that we can't get away with things (“The Lord is coming back! Look busy”). It's a reminder that there is a truth about our inner moral condition that can't be spun or smoothed over. We may be only fitfully aware of what it is, but we know that it's there and that we should be concerned about it - concerned about whether we are acting as we do because of what we value. At the very least we are obliged to keep probing whether we're deluding ourselves or making it too easy for ourselves.

People who can be depended on in public life are those who allow us to see clearly what they value and what they might make sacrifices for (not just what they would like us to make sacrifices for). We talk about people's vocations most readily when we see them clearly doing things that don't bring easy rewards. But if the culture is such that regulation takes the place of virtue, we shouldn't be too surprised if public figures show signs of the virus and take refuge in the “no rules were broken” tactic. We trust volunteers in various settings because we sense that they act out of gladness to be doing what they do, never mind the rewards.

If we are to recover trust in our political class, we need to know something about what they're glad to do for its own sake - because, though we often forget it, this is one of the surest tests of virtue.

It would be a tragedy if our present troubles spelt the end of any confidence that politics and public service could and should be a calling worthy of the most generous instincts.

The author is Archbishop of Canterbury

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