It was noisy where I was sitting with X, a professor of Jewish Studies from America, for a chat and a snack. So I thought perhaps I’d misheard when he said: ‘I understand the Germans better now’.

But I hadn’t got it wrong. I sensed at once what he meant: German people in the Hitler years weren’t the only ones to carry on with their lives and not get involved when evil was happening at – and within – their borders. We’re capable of doing that too. It’s not a pleasant thought to let into one’s mind. Of course, there are radical difference in degrees of evil, the paralysing effect of fear and, no doubt, many other factors.

‘There are children of five and under’, my friend continued, ‘separated from their parents in detention centres near the US borders, living in their own excrement. The physical and mental trauma will never go away’.

Next day I received an email from a friend, now in another country:

We have a choice to see how today’s events pan out in history. Get out there, fight for [the democracy] we have. We cannot stand quiet. Make it clear there is a side for good and a side for evil. If alternatively you prefer to get that hoped for role of Kapo in the future state where all those moaning do-gooders like me will finally shut up about all those things that annoy you (Human Rights anyone?), please defriend me.

I wouldn’t have used exactly that language (you should see some of the political comments which, as a rabbi, I left out). But I feel no less strongly.

For two thousand years our teachers have understood the danger of moral indifference. The rabbis took the Torah’s instruction ‘You may not stand idly by your brother’s blood’ as a commandment never to be a mere onlooker in the face of evil.

Evil is not endemic in our society. But it has roots, and shoots which look like growing: ignorance among the rich and comfortable of the life of the poor; hostility to ‘outsiders’ (not excluding Jews); contempt for the environment; shamelessness and disdain for truth and integrity in high places; unbridled consumerism for which our children will pay the real price.

Good is also all around us: letters and emails from organisations and individuals courageous in compassion pour through my letterbox and into my inbox. As the Torah says: the choice has been set before us.

Abraham Joshua Heschel once thought he’d spend his life as a spiritual teacher, serving ‘in the realm of privacy’. Three considerations changed his attitude. The first was the inability to sustain inner stillness in the face of what was happening around him. The second was ‘the discovery that indifference to evil is worse than evil itself’. The third was the impact of the outspoken moral courage and visceral compassion of the prophets of the Hebrew Bible, on whom he wrote his PhD in Berlin, precisely as Nazism was tightening its hold on power:

There is immense silent agony in the world, and the task of man is to be a voice for the plundered poor, to prevent the desecration of the soul and the violation of the dream of honesty.

I think of these words alongside those which the biblical Mordechai passed in secret to his protegee Esther at the critical hour in their shared destiny, knowing even as he did so that it would be hard for her to act on them: ‘If you remain silent now…’

There are innumerable issues which go to the heart of justice and compassion. The only illegitimate choice is to engage with none.