"When he arrived in Ireland, Patrick realized that he needed to convert the pagan king Laoghaire at his headquarters in Tara. The druid priests were infuriated and in that violent time, they tried to kill Patrick and his companions. In an extraordinary succession of adventures, Patrick escaped these attempts to kill him, such as when he passed by a group of assassins, unharmed, because he had become invisible. (When his little group escaped, they composed the famous "Breastplate of Patrick" prayer)
Later at a banquet at Tara, Patrick and his five companions astonished the king by suddenly appearing at table after passing through locked doors. After the king invited Patrick to sit next to him, the chief druid laced Patrick's drink with poison. Patrick made the sign of the cross over the cup and his beverage froze, except for the drop of poison. Patrick proceeded to pour the poisoned drop out onto the table. Then, after he blessed his cup, he drank the potion without dying.
This encounter was followed by other tests. Patrick made snow disappear, turned darkness on a plain into light, and last of all, conquered the druids in a trial by fire in which one druid was placed in a wooden hut while one of Patrick's followers, covered by Patrick's cloak, was placed in a second hut built of dried out wood (the druid's hut was freshly cut). Both huts were torched and Patrick's follower emerged unharmed, and Patrick's cloak was not even singed.
This dramatic power encounter still wasn't enough to convert the king, but it did impress him enough to give Patrick permission to preach. As a result, within a few years Patrick had baptized tens of thousands and built hundreds of churches. By the time of his death, Ireland had mostly abandoned the druid religion and had become Christian."
No shamrocks and leprechauns for me...but I'll celebrate a life lived for God any day..."