Martin Luther must be turning in his grave. Not only is the Pope about to attend a commemoration of the event nearly 500 years ago that was to kick-start the Reformation and eventually tear Christianity apart, but there are even whispers in Rome that Francis might be about to overturn the excommunication of a man regarded for centuries as a heretic.  

Welcoming Luther back into the Catholic fold posthumously would be seen as a landmark gesture of mercy in the jubilee year that will end next month. It’s probably further than even the generous Francis will go, but the fact it’s being spoken of here is an indication of how conciliatory this Pope is – particularly where Christians of other denominations are concerned.

Next week Francis will travel to Lund in Sweden to participate side by side with Protestant leaders in events that will mark the start of the Reformation – and this itself has been controversial among some hardliners in the Vatican. Conservatives here were angered recently when the Pope met Lutherans in a room that contained a statue of the German Augustinian friar who on 31 October 1517 – tradition has it – nailed 95 theses critical of church practice, particularly in regard to the sale of indulgences, to the door of the castle church in Wittenberg. Just over three years later, Luther was formally excommunicated by Pope Leo X.