Virgo prudentissima is the Magnificat antiphon at First Vespers of the Feast of the Assumption (Aug. 15).
The setting by Isaac adds a long trope in honor of Maximilian I.
Settings by composers
Text and translations
Virgo prudentissima, quo progrederis, quasi aurora valde rutilans?
Filia Sion, tota formosa et suavis es:
pulchra ut luna, electa ut sol.
Virgin most wise, where are you going, shining out as brightly as the dawn?
Daughter of Sion, you are most comely and merciful,
beautiful as the moon, excellent as the sun.