O Salutaris Hostia is a prayer that is sung during the Exposition of the Blessed sacrament. It is the last two stanzas of Verbum Supernum, a Eucharistic hymn composed by Saint Thomas Aquinas.


O SALUTARIS Hostia
Quae coeli pandis ostium.
Bella premunt hostilia;
Da robur, fer auxilium

Uni trinoque Domino
Sit sempiterna gloria:
Qui vitam sine termino,
Nobis donet in patria.

Amen. 

O SAVING Victim opening wide
The gate of heaven to all below.
Our foes press on from every side;
Thine aid supply, Thy strength bestow

To Thy great name be endless praise
Immortal Godhead, One in Three;
Oh, grant us endless length of days,
In our true native land with Thee.

Amen. (tr. E Caswall) 

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