POST-CHRISTMAS and New Year we all want to lose weight, drink less, exercise more. The excess of the last month builds up guilt which we hope to shed along with the pounds, writes the Rev Canon Angela Tilby, continuing ministerial education adviser at the Diocese of Oxford.

Last year there was a fad for diets based on vegetable juices.

I dutifully went to the supermarket and juiced together a whole pile of green stuff, including avocados and kiwi fruit. It was supposed to see me through for several days but the first glass was so disgusting that I poured the rest away.

This year I am not going to try anything so ambitious. I have found a regime which seems to suit me, based on not being extreme – though I find I can do without too many carbs and sugar more easily than without butter and oil and cream!

What is interesting though is the longing we seem to have at this time of year to eat fresh and green things. Sprouts, cabbage, kale, spinach.

As though we sense that our bodies are getting depleted as winter wears on and we need to renew ourselves from within. After the season of feasting there is an appeal in simplicity. But perhaps we rush into this too quickly. Here the Christian calendar is more generous than the secular one. The season of fasting, Lent, is not immediately after Christmas.

This year it begins in the middle of February, as though the Church knows a regime which starts too early and is exclusively concerned with diet and exercise will be hard to stick to.

How do we find within ourselves greater generosity, courage, resilience, forgiveness?

Those are fruits of character and they need cultivating, like the green shoots that will soon begin to appear in our gardens.

There is a spiritual exercise which anyone can do, no matter what your beliefs or lack of them.

At the end of every day spend a few minutes reviewing what has happened, the things you have done, the meetings, the conversations, the things you have noticed around you.

Trace your actions and reactions and note those points in the day when you felt energised, motivated and free. Think what it was that produced those feelings, because this is a chance to identify growth and potential within yourself.

Then review the day again and note those moments when you felt depleted, anxious or constrained. This is where you have spiritual work to do.

The medieval Abbess and theologian Hildegaard of Bingen spoke of viriditas, greenness, as a spiritual quality most to be desired. It is the freshness in creation and in the human soul which brings life.

So eat up your greens and seek the greenness within – and lose a few pounds without even noticing.