ARCHBISHOP Martin held up a silver-framed photo which had been on display on the mantelpiece behind him, and regarded it fondly. It was a picture of himself deep in conversation with Pope Benedict XVI.
"This was taken just before the Eucharistic Congress," he explained enthusiastically, explaining that the Pontiff had been quizzing him on the upcoming Congress (which took place in Dublin last June) and on how the church was doing in Ireland.
The photo showed two men relaxed in each other's company – and well they might, given that their friendship goes back quite a distance, as the Dublin cleric has spent a large part of his career in the Vatican.
Diarmuid Martin explained that the two of them always spoke in German (the archbishop speaks five languages) when they met. But on that occasion last summer, he said, "when I saw him in the car, I realised how old he'd got. But he got out of the car and came straight over to me and he was straight into the conversation," he added.
"Did it come as a shock to you all?" he asked the reporters who had assembled for the press conference in the Archbishop's Palace in the wake of the news of the Pope's resignation. It had indeed come as the proverbial bolt from the blue to most of the Catholic shepherds and flock – but not perhaps so much to Diarmuid Martin who remarked that there had been "small indications" that such a dramatic move was in the offing.
But then Dr Martin has sources aplenty in the Holy See, for he spent three decades as a Vatican diplomat before being handed the poisoned chalice by Pope John Paul II in 2004 to return to his native land and spearhead the clean-up of the Catholic Church in the wake of a string of child sex abuse scandals.
But his robust approach to his task didn't please everyone in the Roman curia, and his star has waned in the corridors of papal power in recent years.
And yet yesterday the archbishop insisted that under Pope Benedict the attitude of the Vatican to the scandals "changed significantly – (the Pontificate) took a much stronger line in addressing these issues."
Dr Martin paid tribute to the Pope's "courageous" decision to resign, describing him as a "reserved person. I remember him as a cardinal – he led a very simple life. I would say of all the cardinals I knew, his personal lifestyle was the simplest. His sister looked after him until she died very suddenly and very tragically and he was not a man for social life. He was much happier when he was writing and preaching," he said.
He also believed that "there's a stereotype of the Pope present in Ireland which is an unfair one.
"He is certainly very concerned about the church in Ireland and he certainly showed that on many occasions when I met with him and when he met with the Irish bishops," he said.
The archbishop said that when he attended the Synod of Bishops last October he noticed that the Pope "had a slight fear in walking and watching steps". But his speeches were a different matter, said Dr Martin. "He would go on with remarkable insights and was very relaxed.
"He never missed the free discussions in the evenings. It's all very different to the stereotyped images of the man," he said.
Dr Martin recalled how he got to know then-Cardinal Razinger when he lived in a German establishment in Rome, where the German prelate came to preach on a regular basis.
"He was very much a man of God. His homilies were astonishing – he would speak without any notes for 45 minutes and you saw the depth of this man. You see that now, that his resigning means that there was nothing he was doing there which was focused on himself. To do this it shows he has interior freedom within himself to do that," he added.
Almost immediately after Pope Benedict's stunning announcement, the speculation began over who would succeed him when the Papal Conclave meets next month. But Dr Martin is far too shrewd an operator to pick a favourite at this early stage.
"We'll see," he said cagily. "Even though most of the cardinals were appointed by the outgoing Pope, they don't clone his successor, very often, anything but."
While Cardinal Sean Brady will be the only Irish prelate to cast a vote in the Conclave, there's no doubt that Diarmuid Martin will be following this election with greater attentiveness than most. For as a long-time crew-member of the Holy See, he knows that stars can rise again just as quickly as they fall.