reform of the Church, the spread of Protestant doctrines in the West, and Turkish armies advancing from the East. Church discipline Aware of the necessity of restoring discipline and morality at Rome to ensure success without, he at once proceeded to reduce the cost of the papal court after the manner of the Dominican Order to which he belonged, compel residence among the clergy, regulated inns, and assert the importance of the ceremonial in general and the liturgy of the Mass in particular. In his wider policy, which was characterised throughout by an effective stringency, the maintenance and increase of the efficacy of the Inquisition and the enforcement of the canons and decrees of the Council of Trent had precedence over other considerations. Liturgy Accordingly, in order to implement a decision of that council, he standardised the Holy Bible by promulgating the 1570 edition of the Roman Missal. Pius V made this Missal mandatory throughout the Latin rite of the Catholic Church, except where a Mass liturgy dating from before 1370 AD was in use. This form of the Mass remained essentially unchanged for 400 years until Pope Paul VI's revision of the Roman Missal in 1969–70, after which it has become widely known as the Tridentine Mass; use of the last pre-1969 edition of the Missal, that by Pope John XXIII in 1962, was permitted without limitation for private celebration of the Mass and in July 2007, was allowed also for public use, as laid down in the motu proprio Summorum Pontificum of Pope Benedict XVI. However, in July 2021, Pope Francis issued a new motu proprio, Traditionis Custodes, which abrogated Summorum Pontificum and reinstated the restrictions on the celebration of 1962 Missal. Thomism Pius V, who had declared Thomas Aquinas the fifth Latin Doctor of the Church in 1567, commissioned the first edition of Aquinas' opera omnia, often called the editio Piana in honor of the Pope. This work was produced in 1570 at the studium generale of the Dominican Order at Santa Maria sopra Minerva, which would be transformed into the College of Saint Thomas in 1577, and again into the Pontifical University of Saint Thomas Aquinas, Angelicum in the 20th century. Holy League Pius V arranged the forming of the Holy League against the Ottoman Empire, as the result of which the Battle of Lepanto (7 October 1571) was won by the combined fleet under Don