In one of his last sermons, the great Christian theologian and philosopher Paul Tillich asked: “Do we have a right to hope?” As an army chaplain to German forces during the first world war and a refugee from Nazi Germany, Tillich had witnessed first-hand some of the horrors of the 20th century. But his answer to the question he posed in 1965 was yes. Nobody could live without hope, Tillich told his Harvard audience, even if it led “through the narrows of a painful and courageous ‘in-spite-of’”.

Sixty years on, a similar spirit of defiant optimism is needed to navigate our own era of conflict and anxiety. The fourth anniversary of Vladimir Putin’s invasion of Ukraine is approaching, and dark political forces menace the social fabric of western liberal democracies. More widely, a fracturing multilateral order is delivering a more unstable and threatening world.

According to a report published in June by the Peace Research Institute Oslo, the number of state‑based conflicts in 2024 was higher than at any time since 1946. In Gaza, the declaration of a ceasefire in October has brought partial relief. But amid the ruins, a suffering population remains scandalously short of food and cruelly exposed to the ravages of winter. In Sudan, a relentless and brutal civil war continues to be stoked by outside powers in pursuit of their own interests. The shocking terror attacks at Bondi beach and in Manchester, and a mercifully foiled Islamist plot to launch another attack on British soil, confirm a global rise in antisemitism following the Hamas massacre of 7 October and Israel’s war in Gaza.

Across Europe, fear of conflict is more acute than at any point since the cold war tensions of the 1980s. In her first major speech as the head of MI6, Blaise Metreweli announced a new “age of uncertainty” as Russia and other hostile states refine techniques of hybrid warfare. An end-of-year address by the Nato secretary general, Mark Rutte, in which he suggested that Russia could attack the west within five years, reflected the increasingly febrile mood of the times.

Yet it remains possible to find reasons in the present to believe in better human futures. The selflessness and remarkable courage shown by Boris and Sofia Gurman, a Jewish couple, and Ahmed al-Ahmed, a Muslim, in confronting the Bondi beach gunmen, was inspiring. So too the resolve and endurance of Ukrainians who have lived under Russian bombardment since February 2022.

In Sudan, the resilience and dedication of local volunteers has kept community kitchens going across the country, offering a lifeline amid a desperate hunger crisis. As Tillich observed in a radio broadcast during the second world war: “Love breaks out of the prison of individualism and nationalist stupidity. Love goes to another person, even one with a different language or of a different race, and returns from him richer.”

A sense of the power of collective human endeavour will be felt in quite another way on Wednesday as millions tune in to the Christmas Eve service at King’s College, Cambridge. The choral beauty of the Festival of Nine Lessons and Carols marks for many households the true beginning of the season of peace and goodwill. But it too was conceived against the terrible backdrop of war. Eric Milner-White, who planned the first service as the dean of King’s in 1918, served, like Tillich, as an army chaplain on the western front. Now, as then, the world needs a message of hope in the darkness.

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