Pope St. Pius V
Fr. Alban Butler's Lives of the Saints. 1928.
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Priestly Celibacy
The Emperor Maximilian II wrote to Pope Pius IV to desire that priests might be allowed to marry, as a means that might facilitate the return of the modern sectaries to the communion of the church.
The whole sacred college saw the inconveniences of such an abolition of the most holy and ancient canons; but none spoke more vigorously against it than Michael Cardinal Ghisleri, the future Pope Pius V: