Unable to answer question, because the hymn you are referring to apprently doesn't exist.
WW Phelps is accredited with the following hymns:
Come, All Ye Saints of Zion*
Come, All Ye Saints Who Dwell on Earth*
Come, Let Us Sing an Evening Hymn*
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The Boondock Saints prayer is spoken in Latin. It is a variation of the traditional prayer "In Nomine Patris, et Filii, et Spiritus Sancti" (In the name of the Father, the Son, and the Holy Spirit).