Romania is not actually classed as a poor country, but it's hardly a rich one. It has poor infrastructure, a lot of corruption, a stultifying bureaucracy and an ageing workforce. Having said that, it's getting better quite quickly.

But should it be spending €500 (£420 million) on a new cathedral?

Now nearing completion, it will be absolutely huge. Its dome will be 120 metres high, making it the tallest Orthodox building in the world. It will seat around 6,000 worshipers, and include a soup kitchen able to feed 1,000 people, two hotels and parking for 500 cars.

To be fair, it is competing for attention with the monstrous House of the People designed by dictator Nicolae Ceaucescu. According to the Church, Bucharest needs a "representative National Cathedral" because every other Orthodox country has one and the one used at the moment is too small.

There are a lot of Orthodox Christians in Romania, and the Church isn't short of money. Hundreds of churches have been built since the fall of Communism, partly funded by a generous state (which also pays priests' salaries).

Still: £420 million is a lot of money.

Of course, Romania is not the only country to splash out on a grand church building when it might be argued money could be better spent. Funding arrangements were quite different, of course, but the stand-out example of an ecclesiastical vanity project is the Basilica of Yamoussoukro in Ivory Coast, one of the poorest countries in the world. Completed in 1989 and by all accounts absolutely stunning, it was the brainchild of the country's President Félix Houphouët-Boigny. It cost $300 million, doubling the country's foreign debt, and was built using 30 acres of marble from Italy and 23,000 square feet of stained glass from France. It has 7,000 seats, all individually air-conditioned, and hardly ever has more than a few hundred in the congregation; Yamoussoukro is a small town (Houphouët-Boigny's birthplace), grindingly poor, and the country doesn't have too many Catholics anyway.

But what do these cautionary tales of vast and expensive buildings have to teach us? When does a project ostensibly designed to honour God become fatally compromised by purely human considerations, such as national pride, personal ambition, vaingloriousness and a lack of common sense?

This isn't just a theoretical question. Anyone involved in a church community is going to come up against it sooner or later, though not on anything like the same scale. That's because doing anything lasting and worthwhile takes money, whether it's invested in a building or in a project. And sooner or later compromises will have to be made. Having this quality of carpet rather than that frees up so much money to do something else – give it away to missions, for instance. But what will the missions do with it? They have to make compromises too.

But why not take a a principled decision to build everything as cheaply as possible? The answer is that it might be a false economy, and that – to continue using buildings as an example – a cheap and shoddy building is off-putting to users and so counter-evangelical. And after all, many of the great churches of our own country might have been regarded as extraordinarily ambitious, not to say extravagant, when they were first put up.

So, to return to Bucharest via Yamoussoukro: what might we learn? There are good things and bad.

1. Don't be scared of spending money on beauty

Beautiful buildings and beautiful art can honour God, even when they're expensive. To see art and human need as being in competition is a false distinction. Beauty is a human need as well; our souls need feeding as well as our bodies. There will be times when a choice has to be made, obviously – and obviously, the body's needs have to be met first. But in the long run, they belong together.

2. Build for the future

Whether it's buildings, projects or people, we should be thinking about the next generation, not just our own. That means spending on quality, and laying foundations that will outlast us – and that takes money.

3. But acknowledge human sinfulness

William Golding's novel The Spire is set against the backdrop of the building of a cathedral spire, driven beyond the point of rationality by one man's ambition. The consequences are tragic. The Bible story of Babel has the same theme (Genesis 11:1-9): there's something in human beings that compels them to try to build higher than they can. But building – a church, a ministry – that is driven by pride, a desire to impress, a flawed human need to leave a mark on the world, or an assertion of the Church's power and influence, is not honouring to God, though he may mercifully bless the results. 

It's hard to see God at work in some things his Church does. Visions can become corrupted by personal interest. We can begin by building for him and end up building for ourselves. The larger the dream, the greater our need for humility and prayerfulness.

Follow Mark Woods on Twitter: @RevMarkWoods