‘Be perfect, therefore, as your heavenly Father is perfect’ is how he puts it. He even tells you in the verses that precede this one how to go about it: you have to turn the other cheek; give untiringly to anyone who asks (including to those who would sue you); constantly go the extra mile and show only love to your enemies (Matthew 5.38-48).

It is often claimed, even by those who don’t believe in him as their saviour, that Jesus offered great moral teaching. C. S. Lewis though cautions against seeing Jesus as simply ‘a great human teacher’ when, in Lewis’s eyes, he was far more besides. I would, however, invite Christians to consider whether the moral guidance Jesus provides here in Matthew’s gospel – how to be perfect – is in any sense ‘great’. If you think it is, because Jesus is Lord, a perfect being and possibly God himself, then you need to explain why it is never followed by Christians, and never has been. You need to explain why you yourself do not apply it in your life, because as sure as poached eggs is poached eggs, you do not. You do not give to all who ask; you do not invite insult after insult and violence on top of violence; you do not give away valuable and essential possessions when threatened with legal action – you are actually more likely to do the suing. And lest you think I am advocating a far more exacting morality for Christians than I would from anyone else, you will bear in mind, won’t you, that is not I who insists on it, but your Saviour. It’s not unreasonable under the circumstances to expect to see you obeying him.

As it is fairly safe to assume you don’t, I would further invite you to consider whether instead of being ‘great’, Jesus’ teaching is in fact unreasonable, unrealistic and impractical. If you are honest, you will acknowledge that it is all of these things, not great or timeless at all, and that is why you, and all other Christians worldwide, disregard it. Jesus’ moral teaching is no more than a series of reckless suggestions, a formula that applied can lead only to poverty and abuse, not perfection. You are probably wise to ignore it and to spend your time instead opposing gay marriage and judging the rest of us.

Revised from ‘Be Perfect’ in my book, Why Christians Don’t Do What Jesus Tells Them To …And What They Believe Instead, available from Amazon.

Notes: C. S. Lewis on Jesus as ‘great human teacher’: Mere Christianity (1952) William Collins & Sons, Glasgow, p52.