Tim Sheppard explores the biblical meaning of 'church' .

Tim Sheppard qualified as a doctor from Guy's Hospital in 2009 and following F2 has worked for a London church as part of their student team.

As Christians we go on and on about church, but why is it worth getting so excited about? When you could be spending more time on the wards saving lives, or conducting an extra research project that would make huge differences to cancer treatment (and your CV), why commit to getting involved with a church? With every new hospital placement it's a huge cost to try to get to know a new church family. Is it really worth all the effort? Surely being a Christian is about being 'saved by grace through faith', (1) not church attendance?

Others of us will have a more panicked approach, fearing that a weekend shift will prevent us from making it to church and therefore leave us further away from God. We find ourselves anxious that our passage through the pearly gates depends on having consistently taken up our spot in the pew. The problem with these extremes is that neither leaves us with the right impression of church; and it's only by correctly understanding what the church is - and what it isn't - that we'll come to see how thrilling church really is.

Retiring old definitions

Most of us use the word 'church' to refer to the building in which a group of Christians gathers on a Sunday - 'It's over there next to the church'. Indeed, the definition of 'church' in the Oxford English Dictionary starts with 'A building for public worship'. (2) 'Church' has become one of a collection of terms used to describe religious buildings, a bit like a temple.

Actually, the word that our Bibles translate as 'church' simply means 'gathering'. It's the same word that is translated 'assembly' in Acts 19 to describe a mob (v32), a court (v39) and a crowd (v41). A church - specifically a Christian church - is a gathering of Christians.

The problem with understanding church as a temple in which Christians meet is that it gives the wrong impression. At best, it simply implies that church is necessary in order to get close to God. At worst, it leaves us thinking that we come to church in order to make sacrifices to God and secure our relationship with him.

Yet the Bible makes it abundantly clear that our access to God has been fully, finally guaranteed by Christ's death on the cross. We no longer have a physical place that we have to go to in order to access God, but if we have put our faith in Jesus we can confidently approach him wherever we are because of what Jesus has done. (3) Incredibly, you don't need to move in order to pray; Jesus has made it possible for you to draw near to God right now. (4)

And yet, in the very same passage of Hebrews where that point is made absolutely clear, the writer encourages Christians to gather - to 'not [give] up meeting together, as some are in the habit of doing' (Hebrews 10:25). Why?

Redefining the church

To understand why the writer adds this, we need to understand more fully what the church is.

The Bible has many ways of describing the church, including the bride of Christ, (5) a pillar that upholds the truth, (6) and a body. (7)

Unfortunately there isn't space here to consider all of these in detail. However, one of the most useful places for understanding the church is Ephesians 4:1-16, where we find three complementary pictures of the church.

a) The church is one body

Ephesians 4:4-6 gives a wonderful sense of the unity enjoyed by all Christians. It is impossible to read the verses and miss the repetition of the word 'one' and 'all'. Paul is absolutely clear that Christians find themselves incorporated into a single united whole; indeed, it forms the basis of his command to '[bear] with one another in love' (Ephesians 4:2).

It's easy to forget this when we gather as a church. We seem almost pre-programmed to concentrate on our differences, and it doesn't take long for our dissimilarities to become the focus of our attention. As medical students, our experience of university can involve a large group of like-minded people of the same age with similar academic abilities and interests. In comparison, church feels like a rag-tag bunch of misfits who couldn't find anything better to do on a Sunday morning.

But actually we share more in common with other Christians than anyone else in the world. The Bible persistently refers to Christians as 'brothers and sisters' because we are all part of one family. The pensioner at the front of church and the mother of five who you barely know share more in common with you than the non- Christian students in your year. As Ephesians 4 says, we are one 'body', each indwelt by the same Spirit, looking forward to the same hope, trusting in the same Lord ... the list goes on. (8)

b) The church is a gym

But Paul has yet more to say. He goes on to show that, in spite of our unity, we each have a contribution to make.

Ephesians 4:11-16 speaks of God giving the writers and teachers of the Bible 'to equip his people for works of service, so that the body of Christ may be built up' (Ephesians 4:12). Picking up on his 'body' metaphor for the church, Paul says that the body is built by 'works of service'. But notice that it is the people who do the works of service, not just the Bible teachers.

So what are these works? The subsequent verses make clear that these works involve 'speaking the truth in love ... [so that] the whole body, joined and held together by every supporting ligament, grows and builds itself up in love, as each part does its work' (Ephesians 4:15-16).

Rather than a temple, the local church is much more like a gym - doing some bodybuilding for the body of Christ. That doesn't mean we need to start installing weights and rowing machines into our church buildings.

Rather, it means each taking on our responsibility to speak the truth in love. It's easy to think that as long as the church leader is there, and someone to lead the music, it doesn't really matter who else turns up, or what I do if I'm there. Ephesians 4 says that each part needs to do its work for the body to be built, and that the work is speaking the truth in love.

That certainly puts the brakes on when I'm tempted to leave during the last song! The church gathering has only just got into the swing of things when the meeting ends. But when I turn to my neighbour and share something that I was struck by from the sermon, I've started doing the kind of work that builds Christ's body.

c) The church is a masterpiece

Perhaps this 'body' doesn't seem all that worth investing in. We're probably all aware of weaknesses and failings in the churches we have visited. There will be no such thing as a perfect church until Jesus comes back. Whether it's the deep roots of past mistakes or the present battles that rage between Christians who still sin, church may seem like a terminal case that would be better treated as a dying patient.

But the Bible's view of the church is much more exciting. It may not look like much yet, but the end goal for the church is described in Ephesians 4:13 - 'we all reach unity in the faith and in the knowledge of the Son of God and become mature, attaining to the whole measure of the fullness of Christ.'

The dizzying height of maturity for which we long is not an impossible pipedream, but simply the masterpiece at the end of this road we call 'church'. Our local gatherings of believers are a foretaste of what we will enjoy in eternity when Jesus comes back - when the spots and blemishes will be washed away. Meeting with other Christians is the closest we get to seeing what it will be like in eternity - which might seem terrifying when you think about your local congregation, but helps me to see the value in investing in them. To serve the growth of the church is to invest in an incredible building project.

The alternative is devastating. Without the support of a truth-speaking church, Christians are 'tossed back and forth by the waves, and blown here and there by every wind of teaching and by the cunning and craftiness of people in their deceitful scheming' (Ephesians 4:14). Without the encouragement of other Christians, we are prone to listen to false teachers (9) or our own cold hearts, (10) and fall away from Christ.

Yet with the warmth of other Christians by our side, we are grown into mature disciples of Jesus. We, alongside other Christians, are kept until the last day. The body is built, we become increasingly united, and we come to know Jesus better. Indeed, that vision of perfect unity under Jesus is the very thing for which God has been working since before the creation of the world. (11) It's hard to think of something more worthwhile than joining the same project God has been working on since before creation!

I guess it's plain that we're not there yet. But that's why we desperately need church.

A health-check on our attitude to church

Being a medical student inevitably means a lot of moving around. Your next placement may be in a different county - or even a different country. With so much upheaval, it's easy to forget the importance of gathering with church family. But the more we understand what God has explained to us about church, the more we'll want to commit to serving in a local church family - to building up a body, and being built up with it.

Here are a few things you might want to ponder when considering church:

1. Find a church that loves Jesus and teaches the Bible. With so much choice when we move house, it's easy to lose track of what's most important. It may be that we prefer a particular style or don't want to travel too far, but what's most important is that we find a church that will point us to Jesus, and give us the Bible teaching and fellowship that allows us to speak the truth in love to one another.

2. Don't give up meeting together. There will always be times when it is impossible to join our brothers and sisters on a Sunday, but avoid making a habit of it. Make sure that gathering with other Christians is a priority. If a weekend shift means I haven't been able to join the normal regular meeting, why not take another opportunity this week to meet up with some of them instead? Seeking out a church that offers regular midweek activities in addition to meeting at the weekend inevitably makes this a lot easier.

3. Commit to serving in the church. Remember that the gathering is not just for your sake, but for the rest of the church family too. Each part needs to work for the body to grow, and that means they need you!

4. Stop looking for perfection. Whenever we visit a church, we'll notice the things that are wrong with it - but how are they doing on the things that matter? And once we've found a church that is doing ok on those, we should stop shopping around and stick with it.

5. Remember that church is irreplaceable. Lots of other things may look like church, but nothing can replace it. We may enjoy listening to a worship CD, or gathering with other medics in a CMF group, but neither of these replace the normal pattern of gathering with a range of believers to be fed from the Bible and pray together. Even another local church isn't a complete replacement for my own church family. It's not about getting my fix on a Sunday, but gathering together with other Christians to be encouraged and to encourage others, 'and all the more as you see the Day approaching' (Hebrews 10:25).