According to The History of the Irish Race by Seamus MacManus, the following is the sacred prayer or hymn chanted by Patrick and his missionaries as they were marched to Tara to face the pagan king there.  He wrote it, the first such work in Gaelic. 

It worked.  Before the king, his Druids and the assembled multitude, Patrick spoke and preached. He converted them all, save the king. But the monarch gave Patrick freedom to preach throughout his realm.  Down through the years, the Irish have used Patrick's prayer of protection in times of trouble. 

I bind to myself today

The power of Heaven,

The light of the sun,

The brightness of the moon,

The splendor of fire,

The flashing of lightning,

The swiftness of the wind,

The depth of the sea,

The stability of earth...

God's power guide me,

God's wisdom teach me,

God's eye to watch over me,

God's hand to guide me,

God's shield to shelter me,

God's Host to secure me...

Against everyone who

Meditates injury to me,

Whether far or near,

Whether the few or the many.

 

John B. Dwyer   3 17 07