The Council of Trent closed on 4 December 1563 after eighteen years and three separate periods of session, and Pius IV confirmed its decrees the following month. Confirming them settled what the Roman church taught; it did not settle how anyone would be held to it. The profession promulgated on 13 November 1564, in the bull known from its opening words as Injunctum nobis, was the instrument for that, and its structure carries the whole intention.
It begins with the Niceno-Constantinopolitan Creed, word for word, the text every party to the sixteenth century quarrel already accepted. Then it continues in the same first person singular voice, without a break in the grammar, into the matters nobody agreed on: the apostolic and ecclesiastical traditions, Scripture read in the sense the Church holds and by the unanimous consent of the Fathers, the seven sacraments, the Tridentine decrees on original sin and justification, the mass as a true and propitiatory sacrifice, transubstantiation, communion under one kind, purgatory, the invocation of the saints and the veneration of relics and images, indulgences, and true obedience to the Roman Pontiff as successor of Peter.
The effect of joining the two halves is that a man swearing the second is swearing it in the same breath as the first, and cannot separate the ancient faith from the Tridentine one. It was required of bishops on taking office, of clergy holding benefices, of teachers and graduands in Catholic universities, and of converts received into the Roman church. Trent had spoken as a council about doctrine; this made each person answer for it individually.