Hymn for Vespers and Lauds for the Common of Holy Women. It was written by Cardinal Silvio Antoniano (1540-1603). Nine translations are in existence. The one given in Britt is by E. Caswall, the fourth verse reads:
O Christ, the strength of all the strong;
To whom our holiest deeds belong.
Through her prevailing prayers on high,
In mercy hear Thy people's cry!