This is the text of this morning's Thought for the Day on BBC Radio 4's Today programme:

In the middle of last week I got back from a ten-day visit to Tanzania. Not only are my feet still moving to the rhythms of the music and the energy of the dancing – in schools as well as churches – but I have come home looking differently at what had previously been familiar.

My experience reminded me of the late German Chancellor Helmut Schmidt who wrote a book several years ago in which he kindly offered his advice to anyone thinking of standing for election to the German Bundestag: don't even think about it unless you speak at least two foreign languages to a competent degree. Why? Well, because, he says, you can't understand your own culture unless you look through the lens of another culture – and to do that you have to know something of (or, better, 'inhabit') the language. After all, language goes deep and some things can't be translated; they have to be intuited.

Well, I don't speak Swahili, but this is partly what was going on for me in Tanzania: not everyone sees the world as I do. For example, how are we to understand the significance of the first meeting in a thousand years between the Pope and the Patriarch of Moscow last week? Seen through an English lens, it might look merely odd. Seen through the eyes of a people whose religious memory goes deeper into centuries of division, and it will resonate more profoundly.

Or, politically, where the resurgence of Putin's Russia appears threatening in the West, but has a different complexion when seen by Russians whose recent history of collapse has been crying out for re-empowerment. Tensions over Syria, for example, have to be seen through Russian eyes, not just our own, if we are to see more clearly what is going on there.

None of this is new. Listening to Tanzanians describing their experience of life and loss, I could not help but look through their eyes at my own. And this exposes the limitations of my own imagination and understanding of the world – even my world. My mind was being changed.

This is what is referred to in the Bible as 'repentance' – the freedom to change one's mind – or, to put it more visually, to re-grind the lens behind the eyes that shapes the way we see God, the world and us.

It is no surprise, then, that for Christians this period of Lent is intended partly to clear away the stuff that stops us repenting. It creates the space in which we can once again, in humility, submit our perceptions, our convictions and our prejudices to the searching eye of love and justice and mercy and generosity. Or, for Christians like me, to have the courage not just to give up chocolate for a few weeks, but to dare to look and see differently that with which we had become comfortable or familiar.