Like many evangelicals I was stunned to find Steve Chalke lining up with those who want to make the case for same sex marriage. His 'coming out' was a total surprise and I was left feeling disappointed, both by his stance and his timing.

As Peter Saunders of the Christian Medical Fellowship noted "he has clearly chosen deliberately to take this controversial stand at this time and in this way in an attempt to influence the upcoming parliamentary debate on gay marriage".

Chalke of course is no stranger to controversy. The mere mention of his name will revive memories of the furore that followed his oft-quoted remarks on the subject of penal substitution. He lost a lot of evangelical support then and is likely to lose a lot more now.

I've been intrigued to notice the varying responses to his shock disclosure, which have ranged from disappointment to sadness with varying degrees of criticism and even cynicism. Having said that, lots of commentators seem to have gone out of their way to pay tribute to his past contributions as well as his critique of the homophobia that seems endemic in evangelical churches.

However we need to recognise that Chalke's outspoken contribution does raise fundamental questions about the way we handle controversy within the church and how robust we feel we can be when dealing with what Peter Saunders rightly claimed is 'heresy'.

Just over eight years ago, when discussing Chalke's understanding of the atonement, the Evangelical Alliance's Joel Edwards said he wanted "to be part of a grown-up evangelical community which exercises robust love", and that he had no wish to be part of or to lead "a group of Christians who panic in the face of controversy, retreat from each other or condemn each other without conversation".

We need to adopt a similar approach today. Steve Chalke has exercised a significant influence over the evangelical community. He cannot and should not be allowed to say the things he has said without robust confrontation. This need not be offensive nor personal, but we cannot avoid the fact the NT evidence clearly supports this sort of reaction to false teaching.

Thankfully we are not enjoined to stone false prophets, as the Israelites were in the days of Moses. Everything we say and do must be conducted in an atmosphere of love in the hope that we will convince him of the error of his ways. But we must not avoid calling a spade a spade. Jesus for example could be very direct (which of us would like to be compared to a whitewashed tomb?) In the same way the apostles insisted that we should not only fight for the faith but we must not even welcome false teachers into our homes (see Jude 3-4 and 2 John 19-10).

This is not to say Steve Chalke is no longer a Christian. It does not mean that we have to ignore the immense contribution he has made to the Kingdom of God, nor the significance of the pastoral challenge he has brought us (although he is not the first to highlight the evangelical tendency to homophobia).

But it does mean that we recognise the preservation and transmission of Biblical truth from generation to generation will not only result in controversy but demands a robust response when Biblical truth is either rejected or distorted. After all, he has not been shy in telling us what he believes.