The composer Wolfgang Amadeus Mozart was a Catholic, and the Church played an important role in his life.
Life
Catholic upbringing
Mozart's parents (Leopold Mozart and Anna Maria Mozart) were Catholics and raised their children religiously, insisting upon strict obedience to the requirements of the Church. They encouraged family prayer, fasting, the veneration of saints, regular attendance at mass, and frequent confession.
Leopold Mozart continued to urge strict observance upon Wolfgang even when the latter had entered adulthood. In 1777, he wrote to his wife and son, who at the time were on their journey to Paris:
Is it necessary for me to ask whether Wolfgang is not perhaps getting a little lax about confession? God must come first! From His hands we receive our temporal happiness; and at the same time we must think of our eternal salvation. Young people do not like to hear about these things, I know, for I was once young myself. But, thank God, in spite of all my youthful foolish pranks, I always pulled myself together. I avoid all dangers to my soul and ever kept God and my honor and the consequences, the very dangerous consequences, before my eyes.
By "very dangerous consequences", Leopold was most probably referring to a specific doctrine of Catholicism, namely that persons who die in a state of mortal sin will experience eternal punishment in hell.
Leopold extended another important element of Catholic belief—the existence of earthly miracles as signs from God—to the case of his son, whose abilities he considered to have a divine origin. In 1768, he wrote to his friend Lorenz Hagenauer, describing his son as a miracle, which God has allowed to see the light in Salzburg. ...And if it is ever to be my duty to convince the world of this miracle, it is so now, when people are ridiculing whatever is called a miracle and denying all miracles. ...But because this miracle is too evident and consequently not to be denied, they want to suppress it. They refuse to let God have the honor.
Order of the Golden Spur
As a teenager, Mozart went on tours of Italy, accompanied by his father. During the first of these, Leopold and Wolfgang visited Rome (1770), where Wolfgang was awarded the Order of the Golden Spur, a form of honorary knighthood, by Pope Clement XIV. The papal patent for the award said:
Inasmuch as it behoves the beneficence of the Roman Pontiff and the Apostolic See that those who have shown them no small signs of faith and devotion and are graced with the merits of probity and virtue, shall be decorated with the honours and favors of the Roman Pontiff and the said See. (4 July 1770)
The following day Mozart received his official insignia, consisting of "a golden cross on a red sash, sword, and spurs," emblematic of honorary knighthood. The papal patent also absolved the awardee from any previous sentence of excommunication (unnecessary in Mozart's case) and stated "it is our wish that thou shalt at all times wear the Golden Cross." In the 1777 painting (shown here) known as the "Bologna Mozart", Mozart is indeed shown wearing his knightly insignia.
Mozart's Golden Spur decoration was the source of an unpleasant incident in October 1777, when he visited Augsburg during the job-hunting tour (1777–1779) that ultimately took him to Paris. Following the advice of his father, Mozart wore his insignia in public, and in particular to a dinner arranged by a young aristocrat named Jakob Alois Karl Langenmantel. Langenmantel and his brother-in-law teased Mozart mercilessly about the insignia, and Mozart ultimately was moved to reply very sharply and eventually depart. Thenceforth Mozart showed considerably more caution in wearing his decoration.
Marriage
Matrimony is a sacrament of the Catholic Church, and Mozart was wedded in a Church ceremony. His bride was Constanze Weber; the two were married on 4 August 1782 in a side chapel of St. Stephen's Cathedral in Vienna where they lived.