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

One personal casualty of current travel restrictions is a long-planned trip to Germany in May where I was booked to preach in Eisenach in the church where Johann Sebastian Bach was baptised and where Martin Luther preached. Looming on the hill above the town is the Wartburg – the castle where Luther was held for his own protection.

Today is the 500th anniversary of the event that led him there. He was summoned to the city of Worms where the Emperor, accompanied by the princes, listened to Luther’s defence against accusations of heresy. The Diet of Worms was not, as many children assume, a bad food day; rather, it was more of an inquisitorial court which had the power to condemn a man completely.

The story goes that Luther concluded his defence against the charges with the bold statement: “Here I stand; I can do no other.” Even though there is no evidence that he did actually say this, it sums up his position well and justifies the pair of socks I was given in His home town of Wittenberg that has it imprinted on the sole.

What I find interesting about this episode is that it was Luther’s courage that gave credibility to his position as a reformer rather than purely the content of his theology. People so admired the personal bravery of a man who was willing to deliver himself into the hands of the authorities that they then paid attention to what he was saying.

In other words, character was as important as content when it came to the credibility of his case – what we today call virtue ethics. Luther would not recognise the term, but he exemplified it. He was a complex man who demonstrated the resilience and determination to stand up for the truth (as he saw it in the Bible), but he was also rude, obstinate and difficult. While he was being protected in the Wartburg – and translating the New Testament into German, a work of historical and cultural significance – his colleague Andreas Karlstadt took up the Reformation mantle; but, when Luther emerged a year later, he reversed many of the changes Karlstadt had made.

Luther is recognisable as, fundamentally, a disciple of Jesus. I wonder if, when he was translating the gospels in the Wartburg, he saw in the first followers of Jesus a similar complexity to his own. For the early apostles and Saints were just as complicated, obdurate and contradictory as he was.

Luther stood before the emperor on this day in 1521 not knowing if he would see tomorrow. What his courage demonstrates is that nothing is inevitable in history – that the world is changed by people who embody integrity today – who love truth, even when they have their own limited relationship to it.