Dear Parishioners,
The sins which are essentially opposed to faith can be classified under five headings, namely, Infidelity, Heresy, Apostasy, Skepticism or Doubt, and Indifferentism.
1.  Infidelity: Those who do not believe in Christ’s doctrines are said to be in a state of infidelity.
However, if this happens due to involuntary or invincible ignorance, it is not considered as a sin (cfr. Jn 15:22). The one who knows and refuses to believe is without excuse (cfr. Mk 16:16).
2.  Heresy: The sin of heresy is committed by a Christian who rejects a single truth of faith or obstinately defends a doctrine that opposes any of the articles of faith. Such a Christian is called a heretic.
Also, Schism can be classified under heresy. It is a revolt against the authority of the Church, a formal separation from the unity of the Church.
3.  Apostasy: Furthermore, apostasy is the total abandonment of the Christian faith by a baptized person. It implies at the time a revolt against Christ and his Church. Again, to willfully doubt anything revealed by God is tantamount to call in question the divine truthfulness and can either result in heresy or apostasy.
4.  Skepticism or Doubt: The sin of skepticism or doubt is that attitude by which one questions everything or some elements about faith, not with the intention to be informed but with the aim of waiving them away. An example is the questioning of the doctrine on heaven ending up asking “who has ever gone there to see what happens there” and then rejecting the doctrine. A heretic offers a wrong alternative, a skeptic has nothing to offer.
5.  Indifference: Lastly, as far as the matters of faith are concerned, indifferentism can either be theoretical or practical. The former holds that it is of no consequence what religion a man may follow, either because all are false or because none can be proven to be true. This is apostasy in one who once professed the Christian religion and therefore, is a grave sin. It is also a species of heresy for one who does not know to what denomination he may belong is in fact denies one article of faith: that the Catholic Church is the only true Church. The latter means a growing cold or neglect in the practice or duties of faith. It can be fostered by mixed marriages, reading of secular or anti-religious books, magazines and newspapers.
Regarding the sins against faith, Catholics are exempted from several acts. They should not assist or actively take part in religious services of non-Catholics. However, a passive or merely material presence may be tolerated for reasons of civil duties or honor, at funerals, weddings and similar celebrations if and only if no danger of perversion or scandal arises. Also, Catholics are forbidden to join any society with the following marks: absolute secrecy, blind and unrestricted obedience to the leaders, opposition to God’s Church or to lawfully establish civil government and a self-constituted religious worship. Hence, excommunication is granted to any Catholic who enrolls himself in freemasonry and any secret society. Lastly, Catholics are forbidden to read books that are hostile to faith or to good morals and anti-Catholic books.
Happy Sunday to you all!