I knew that tomorrow would be 9/11, twenty years since the terror attack against America and the horrendous destruction of the twin towers. I knew it in my head. But seeing footage; listening to the voices of people who were there at the time, men, women, wives who took that last call from their husbands; watching the firemen; listening to them speak both then and now two decades later, – that brings 9/11 home at a very different depth. I remember the shock at the time; even three thousand miles away it felt as if the pavement was shaking. The shock remains even now.

Two years ago, in that age when one still travelled easily, Nicky and I visited the memorial at ground zero. What can one say? It’s heart-rending.

For some there has been healing. For others, like the woman filmed as she stared out to sea and said she was still mourning the man she loved most in all the world, the sorrow is scarcely diminished.

Suffering begets compassion. But it often also leads to more suffering, as so many desperate to escape Afghanistan know only too well.

I am sure I can say on behalf of my community that our hearts go out to everyone to whom 9/11 has brought, and still brings, grief and pain.

Tomorrow is also significant in the Jewish year. It’s Shabbat Shuvah, which mediates between the New Year and the Day of Atonement. Teshuvah is usually translated as ‘repentance’. Though accurate, this has, for me at least, a limited resonance, as if teshuvah were always about sin. Teshuvah is more comprehensive than that: it’s a rethinking of how we are in the world; it’s a questioning, a re-evaluation, of what matters.

During the shivah for my father – I can’t believe it’s fourteen years since he died – my teacher Rabbi Magonet came up to me after the prayers as I sat on the traditional low chair and said very quietly, ‘This is about teshuvah.’

At first I was puzzled: was he suggesting I’d done wrong? Then I understood that what he meant was something deeper: This is about what truly matters, why we’re here, what it’s all for.

The questions aren’t complicated. On the contrary, it’s the simplicity which makes them so searching: What am I doing with my life? How am I using the limited time I have here on this earth?

The answers aren’t complex either. The heart doesn’t always need sophisticated terminology: It has love at its core, and sorrow for all the hurt that has so wrongly come to exist in the world. It wants to heal, as a mother longs to protect her child. As the rabbis said: Lev mevin – the heart understands.

The heart is such a small and vulnerable organ to set against all the violence, injustice and pain in the world, planes flown with incomprehensible brutality into towers full of people, bombs, the injuries which cruelty and illness inflict every ordinary day.

Or is it? It has remarkable resilience. It often responds to the worst life can do with the best that it can offer in return. It has depth upon depth of strength. When, all but exhausted, it feels it has no resources left, it finds replenishment through the companionship of friends, in the kindness of others, in wonder, even within the smallest of things, and through that spirit which flows subliminally and invisibly and which communicates without words: I am with you; I am life.

If we can return to those depths, we will know what we have to do with our days and our years.