OSCAR WILDE wrote a heart-rending fairytale, “The Happy Prince”. In it, a swallow befriends the statue of a town’s late prince. From his plinth, the Happy Prince sees his people suffering, and asks the swallow to help them, using the decoration from his statue. The ruby is taken from his sword hilt, the sapphires are plucked from his eyes, and the gold leaf covering his body is torn off by the swallow, to alleviate the plight of the poor. The Mayor walks by, and looks up. Seeing the now ugly statue, he orders it to be pulled down and thrown away.

This story is a great parable for all those people who give of themselves too much. Particularly in vocational jobs, it feels virtuous to work hard and work late, and to be deeply heroic and sacrificial. But what happens to your mission in life if you end up using yourself up?

I know some clergy who reckon that God does want them to use themselves up in service of others. It has even got a theological label — kenosis, or self-emptying — which makes it sound both missional and noble. My fear is that, at worst, this has more to do with ego than with selflessness. Why does it all have to be about you?

YES, you are indeed special and unique, but other people are also special and unique, and are also called to serve, whether that is in church life, through volunteering, or through working in organisations or elsewhere.

In industry, in a country where 21 per cent of 18- to 24-year-olds are unemployed, the culture of overworking is having devastating consequences. Senior people are burning out from overwork, while there is an acute shortage of jobs for entry-level candidates. These exhausted people live in parishes and suffer there. What can those of us called by God to be salt and light do to model a better way? How can we all set a better example about sabbath and work-life balance to everyone we lead, but also to grow the talent around us to divide up the work?

It is true that all this busyness adheres to the law of diminishing returns. Overworking causes stress, which, we know, has a negative effect on sleep. Without good-quality sleep, the ability to form memories and make good decisions diminishes. If the brain is unable, through poor sleep, to file data from any given day, there will be no data from it to mine in future; so, over time, the sleepless get progressively less reliable as decision-makers. And, given what we know about the ubiquity of poor sleep hygiene in our boardrooms, the average leader should not be allowed to drive a fork-lift truck, let alone run an organisation.

BUT help is at hand. There is a handy construct, “ego depletion”, which is all about the battery management of your will-power. That grown-up in your head, the Executive Function, is only human, and gets worn out each day through effort: decision-making, the suppressing of emotions such as annoyance or anger, trying to kick a habit such as giving up smoking or dieting — anything you do that requires the exercise of will-power depletes your battery life, which is why you tend to feel exhausted after meetings with difficult people. But keeping this concept in mind is a great way to regulate work-life balance.

While much of life is wearing, it is also true that much in life can be rejuvenating. Let us assume that the drains on your energy won’t go away: bad weather, transport glitches, annoying people, pointless meetings, etc. You can start topping yourself up by taking more control of your diary, particularly when some of these energy-sappers are wholly predictable.

Apart from trying to avoid them by smoothly diarying them out, however, what could you add back in? Here is a generic list of those research-based boosters that are known to help: sleep, rest, and prayer; water, bananas, and low-GI foods; music, singing, and dancing; beauty, joy, and mindfulness; altruism, friends, and family; the outdoors, views, and perspective; flattery, laughter, and winning.

But what else settles and re-sets you? Diary it all in. Make a list, and deploy your own cheering strategies whenever your mood sinks. You are far too special and precious to be thrown away, and you can be more useful in the longer term by being selfish enough in the short term to keep yourself healthy and well.

Dr Eve Poole is the author of Buying God: Consumerism and theology (SCM Press) and is the Third Church Estates Commissioner.