'We welcome everyone to our church.'

It's a standard bit of Christianese and surely every congregation ought to be able to sign up to it – especially nowadays, when getting people to attend at all is a bit of a struggle.

But when we actually start thinking it through, it's not nearly so straightforward. It begins with that word 'welcome' itself. Far from being a vague courtesy, it turns out to have a weight that sits uncomfortably with the way we use it.

The word's origins are in Old English, 'wilcuma', meaning 'a person whose coming is pleasing'. The original focus is not on the attitude of the host, but on the quality of the guest.

'Wilcumas' brings honour to the house because they are of a certain status. They know how to behave. They are easy to talk to because they share interests and backgrounds with the host. They fit in. Their coming is pleasing because they make people happy in their company.

But what happens when the coming of a person isn't particularly pleasing? That's when the 'welcome' of the church is tested. That's when we find out whether we really mean it.

What happens when a family with uncontrollable small children turns up in an all-adult service?

What happens when a non-standard couple – living together without being married, for instance – arrives?

What happens if they're gay?

What happens when someone attaches himself to the congregation and turns out to be quarrelsome and rude, or have poor personal hygiene?

What happens when someone with relatively liberal views joins a conservative congregation – or vice versa?

What happens when the generational homogeneity is upset, or the racial, or the class?

What happens when a gifted preacher joins a complementarian church, but can't preach because she's female?

If we're honest, when we say, 'Everyone welcome', there's usually an unspoken subtext: 'As long as they're like us.' If the guest is a 'wilcoma', 'a person whose coming is pleasing', we're fine.

But Jesus said, 'If you love those who love you, what credit is that to you? Even sinners love those who love them' (Luke 6:32). Love your enemies, do good to them, he says.

People whose coming is not so pleasing aren't our enemies. But it's easy to act as though they were. They remain on the edge. They never quite fit. Their voices aren't heard and sooner or later they will stop speaking, or shake off the dust from their feet and go somewhere else, as Jesus told his messengers to do (Matthew 10:14).

Welcome is hard. It involves self-examination and self-denial. It means we cannot remain as we are. It is a spiritual discipline. It calls us to venture, to be vulnerable and to change. It means listening for Jesus in the voice of the stranger, recognising him in the breaking of the bread.

'Welcome to our church' is not just a civility. It's a call to strenuous discipleship – because ultimately, it's not our church. It's Christ's, and he ate with tax collectors and sinners, and you and me. 

Follow Mark Woods on Twitter: @RevMarkWoods