The First Vatican Council (Dz. 1792) taught with all precision and clarity what is the object of Faith: “By divine and Catholic faith, all those things must be believed which are contained in the written word of God and in Tradition, and those which are proposed by the Church, either in a solemn pronouncement or in her ordinary and universal teaching power, to be believed as divinely revealed.”
Let us explain the terms of this proposition, which is a model of precision and accuracy.
It is necessary to believe by divine and catholic Faith, that is, with a supernatural faith supported by the authority of God, Who reveals, and that of the Church, which infallibly guarantees the existence of divine revelation.
All that is contained in the written word of God or transmitted by Tradition. This indicates the two sources of divine revelation, that is, Sacred Scripture, which transmits it to us in writing, and Catholic Tradition, which transmits it to us in writing or orally from generation to generation. Most of the Protestant sects do not admit as belonging to the faith but the truths expressly contained in the Holy Scriptures; but this doctrine is entirely false and heretical and as such has been condemned by the Church (Dz. 783-784).
These words also exclude, as an object of divine and Catholic faith, the private revelations that some people in particular may receive. Only they are obliged to believe it with divine faith if its divine origin is known to them with all certainty, by virtue of the prophetic light.
And that the Church proposes as divinely revealed. The proposition of the Church is a condition sine qua non for the assent of our understanding to be an act of divine faith.
The reason is because the testimony of God cannot be known with certainty and infallibly applied to ourselves except by prophetic light (which illuminates only the person who directly receives divine revelation) or by the infallible proposition of the Church, who, by virtue of the special assistance of the Holy Ghost, cannot commit error. For this reason, in the Protestant sects that reject the authority of the Church, there is a real confusion and chaos around the truths that must be admitted by faith, as each one of them believes or rejects what they see fit, with no more guidance than their own whims.
By solemn definition. It is one of the ways—the clearest and most explicit—of proposing to the faithful the truths of the Faith. It takes place when the pope defines ex cathedra some dogma of faith or expressly declares it by an Ecumenical Council presided over and approved by the pope.
Or by its ordinary and universal Magisterium. It is the other way in which the Church proposes to the faithful the truths to be believed with supernatural or divine faith. It consists in the common and universal teaching of a certain doctrine by all the bishops and doctors scattered throughout the world. This universal teaching cannot fail or contain any error, by virtue of the special assistance of the Holy Ghost, who cannot allow the entire Church to err in some doctrine relative to faith or morals.
When the Church, whether by solemn definition or by her ordinary and universal Magisterium, proposes to the faithful some truth to be believed as revealed by God, that truth acquires the name of dogma. Consequently, a dogma is a truth revealed by God and proposed by the Church as such.
By the simple statement of the precept as it is read in Sacred Scripture (Ex. 20:8-11), it can be seen the rigor and severity with which the Old Law prescribed the sabbatical rest. The Israelites sometimes interpreted it in a way that was too literal and material, as Our Lord Himself pointed out (Lk. 13:14-16). The Law of the Gospel, while maintaining the precept of the Decalogue, has softened its practical interpretation, as St. Thomas Aquinas explains: “In the New Law the observance of the Lord’s day took the place of the observance of the Sabbath, not by virtue of the precept but by the institution of the Church and the custom of Christian people. For this observance is not figurative, as was theservance of the Sabbath in the Old Law. Hence the prohibition to work on the Lord’s day is not so strict as on the Sabbath: and certain works are permitted on the Lord’s day which were forbidden on the Sabbath, such as the cooking of food and so forth. And again, in the New Law dispensation is more easily granted than in the Old, in the matter of certain forbidden works, on account of their necessity, because the figure pertains to the protestation of truth, which it is unlawful to omit even in small things; while works, considered in themselves, are changeable in point of place and time” (II-II, 122.4 ad 4).
As stated by the Code of Canon Law, on Sundays and feast days, the Church prohibits servile work, legal acts and public trade, shopping, etc. (Can. 1248).
Servile works are those which ordinarily require the exercise of physical force, as those executed by farmers, day laborers, masons, carpenters, etc. The servile works should not be judged by the purpose of the person doing them or by the physical fatigue that they cause, but only by their own nature; thus, they do not cease to be servile even if they are done for simple recreation and without any bodily fatigue.
Thus, on holy days of obligation servile works are prohibited under pain of mortal sin; but dispensations and exceptions are possible.
Legal acts that require certain apparatus and publicity, such as summoning witnesses, holding a public hearing, sentencing, etc., are prohibited on holy days of obligation, but not those that can be done in private, such as consulting, writing a report, giving advice, etc.
Due to the inconveniences that they usually bring for the sanctification of the feast day (difficulty in hearing Mass, excessive profit motive, etc.), the Church also prohibits public markets, fairs, and other public purchases and sales on holy days, unless authorized by legitimate customs or by special permissions granted by the ecclesiastical authority.
In addition to these legitimate dispensations, some other causes may circumstantially excuse the law of Sunday rest, for example:
Piety towards God; thus, it is lawful to work in what is immediately connected with the worship of God, decorate the altars, prepare the litter for a procession, etc.; but not in what has a more remote relation, as repairing the church, making sacred vestments, etc.
Charity for neighbor; thus, it is lawful on feast days to do whatever physical work is necessary to relieve the needs of the sick, etc.
Our own pressing needs; for example, in the case of workers who are required to be at their jobs by their employers, under pain of losing those jobs; the poor to obtain their daily sustenance, the farmers to avoid damage from a threatening storm, the mothers occupied in domestic chores, and other similar cases. But we must be careful to avoid scandal and be sure that there is always a true and proportionate cause, avoiding any self-deception or malice.