It depends on what you mean by celebrate. There may be little harm in drinking green beer, eating corned beef and cabbage, and dancing an Irish jig, but a better celebration would be remembering who Patrick was and what he did for God.
Most people know that March 17th is a day for celebrating Irish national heritage and a man who is said to have rid Ireland of snakes. Many may assume because the title of Saint* precedes his name he was a religious fellow, but few know the real story of Patrick and the role he played in bringing Christianity to Ireland.
Patrick’s story begins sometime in the 5th century. From some of his writings we glean a story of a boy who was raised during the Roman occupation of the British Isles. His father may have been a church leader and a minor community official in Scotland or Wales. When Patrick was a teenager, he was captured by Irish marauders and sold into slavery in Ireland. There, he spent 5 years tending sheep and using his solitude to pray and sing and develop a close relationship with God. He also mastered the Celtic language that became vital for his missionary work later in life.
He escaped from slavery, returned to England and began formal study. Later he traveled to Auxerre in present day France and studied religion under St. Germain. Eventually he was promoted to the priesthood. He believed that an angel told him that the pagan people of Ireland were calling out for his return. With the blessing of the Pope in Rome, he sailed for Ireland and began telling the Druids of the true God and redemption bought at the cross by Jesus. Legend has it that he used the three-leaf shamrock to help explain the Trinity. Legend also says that he drove the snakes from the island, though scientists tell us that there were probably no snakes on the island since the end of the previous ice age.
It is not the legend we celebrate, but rather Patrick’s boldness and fearlessness in preaching the Gospel among a very hostile, pagan people. His missionary efforts led thousands of non-believers to give up their idol worship and become followers of Christ. By the time of his death at the end of the 5th century, the majority of Celts had become Christians.
So Christians and Irish Christians in particular, have good cause to celebrate on St. Patrick’s Day, because they are celebrating the life of a man that God ordained and commissioned to carry His good news to a spiritually dark corner of the world.
*Ironically, St. Patrick, the patron saint of Ireland, and one of the world’s best known saints has never been canonized by the Catholic church and therefore is a saint in name only.