The heart of St. Laurence O'Toole is again on public display six years after it was stolen, and 800 years after the death of the saint.

The relic was stolen from Dublin's Christ Church Cathedral in March 2012 by someone who is believed to have hidden overnight in the building. The relic had been kept in a heart-shaped wooden box behind an iron cage. The thief lit two candles on the cathedral's Trinity altar before leaving, state broadcaster RTE News reports.

After receiving credible intelligence, police found it undamaged in April 2018 following a search in Dublin's Phoenix Park. The heart was promptly returned to the cathedral, but was not put on public display until a new shrine could be built.

Police have tested the reliquary for fingerprints and other evidence but have not yet made any arrests.

St. Laurence was born in 1132 in what is now County Kildare and named Archbishop of Dublin in 1161. He played an important role as a peacemaker during the Anglo-Norman invasions.

He helped establish the Augustinian order in Dublin and reformed the monastic orders in Ireland. He was known for his humility, mortification and prayer.

St. Laurence died in Normandy in 1180, during travels to contact the English king for another peace-making effort. His body was buried in France, but his heart was returned to Ireland. Christ Church Cathedral's Chapel of St. Laud has hosted his heart ever since.

He was canonized in 1225.

Christ Church Cathedral, which has been part of the Church of Ireland since the Protestant Reformation, hosted a special ecumenical service Nov. 14. St. Laurence is venerated in both the Church of Ireland and the Roman Catholic Church, which observes his feast day Nov. 14.

Dublin's Catholic Archbishop Diarmuid Martin celebrated his feast day Mass at St. Mary's Pro-Cathedral.

"Laurence O'Toole was above all a Churchman," the archbishop said in his homily. "In his role of peacemaker that he was forced to undertake as part of his duty, he always appeared as someone different. He was a political figure in a different way: he was a man who sought to change society through the weapons of his Christian faith: prayer, respect, generosity to the less fortunate, appealing to the higher instinct of humankind, and the courage to take concrete steps to do something."