Q. 1. What does the Catholic Church teach about the sin of swearing? Other than using the Lord's Most Holy Name in vain, I never considered swearing as a sin. Some Catholics believe that all forms of swearing are sinful. Is it? Or is it just a personal opinion?
A. 1. First of all, as christians, our every action should serve the purpose of building up the Body of Christ. Swearing does not edify anyone. It does not foster intelligent conversation.
For some people, foul language refers to everything from taking the Lord's Most Holy Name in vain, to cursing, to blasphemy or to just plain old profanity.
According to the Second Commandment of God, “You shall not take the name of the Lord your God in vain.” [Ex. 20:7; Dt. 5:11] More specifically, a person must have respect for God's Name. Throughout the Sacred Scripture, the Name of God is held Sacred. He reveals His Name to those who believe, and through this revelation, invites them to an intimate and personal relationship. How can you have an intimate and personal relationship with God when you keep using His Name loosely as a meaningless form of expression. Do not let this bad habit creep into your speech.
The Second Commandment does not stop at showing respect for the Name of God. We are expected to show respect to all of God's creations, Mother Mary, the Saints, the Angels, using words such as Satan, Hell, making expressiong such as "damm it!", abusing Church related words such as the chalice or the Tabernacle. While these expressions may have become habits, they are a reflection of what is in the heart, a total disrespect for God and His creations.
Regarding those who swear, the Bible says:
“Death and life are in the power of the tongue.” [Prov. 18:21]
Our words are an indicator of what’s in our mind and heart. Jesus said: “From the fullness of the heart the mouth speaks. A good person brings forth good out of a store of goodness, but an evil person brings forth evil out of a store of evil.” [Mt. 12:34–36]
"For by your words you will be acquitted, and by your words you will be condemned." [Mt 12:37]