When St. Lawrence was a child, he was delivered as hostage by his father to the King of Leinster, Dermod Mac Murehad. St. Lawrence was treated inhumanely while he was there. His father obliged the tyrant, Dermod Mac Murehad, to put St. Lawrence in the hands of the Bishop of Glendalough.
St. Lawrence grew up into someone with admirable virtues. In 1150, he was chosen as abbot of the monastery after the Bishop of Glendalough, who was also the abbot, passed away. In 1161, he was chosen to fill the new metropolitan See of Dublin. When he went over to see King Henry II of England, he was received with honor and respect. A few years later, he went back to England to negotiate a reconciliation between King Henry II and the monarch of Ireland. King Henry II was moved by this. St. Lawrence passed away in 1180.