No, what I said is sound Catholic teaching. Willful, conscious stealing - no matter the value - violates the Eighth Commandment and is a mortal sin against the Lord.
According to the Catholic Encyclopedia, stealing something of little value is only a venial sin.
And from the Baltimore Catechism:
Q. 1291. What sin is it to steal?
A. To steal is a mortal or venial sin, according to the amount stolen either at once or at different times. Circuмstances may make the sin greater or less, and they should be explained in confession.
The Catechism of the Council of Trent trumps the Baltimore Cathechism. The latter is not guaranteed to be free of error, hence it’s not infallible. No pope ever officially approved the BC, which was devised by bishops in the U.S. Moreover, the Catholic Encyclopedia’s reference for the “venial sin” teaching comes from 3 theologian sources, hence mere conjecture, not anything defined infallibly such as the Council or Trent.
Nowhere in Trent’s Catechism (unless I overlooked it) does it categorize violating the 7th Commandment (or “8th” in the Septuigant) into both mortal and venial sins. It only mentions the grievousness of stealing, and it says the following: “Hence these words of the Apostle: Neither thieves, nor covetous, nor drunkards, nor railers, nor extortioners, shall possess the kingdom of God.”
http://www.cin.org/users/james/ebooks/master/trent/tcomm07.htmThat is very clear cut.
Again, the categorizing of some types of stealing as venial sins is mere conjecture that was codified in the Baltimore Catechism. It is not taught infallibly, therefore Catholics must err on the safe side and abide what the Commandment says, which is infallibly taught by Trent, “Thou shall not steal”, period, lest you risk losing your soul to perdition. Is willfully and consciously taking a piece of bubble gum that belongs to another person without their approval the act of stealing? Yes. Is it a mortal sin? To answer that question we must identify the conditions that need to be met in order for mortal sin to occur. There are 3 conditions:
1) the matter must be "grave";
2) the sin must be committed with full knowledge;
3) the sin must be committed deliberately.
We can easily agree on the last 2 conditions being met. Now, regarding the 1st condition, some of you are basing your views off of the subjective, which is derived from mere conjecture by American bishops (and, perhaps, theologians), yet not officially approved by any pope nor deemed Ex Cathedra.
Conversely, I base my view off of the objective reality, which is the fact that taking the piece of bubble gum is, indeed, the act of stealing. The 7th (“8th”) Commandment and Trent Catechism clearly forbids the act of stealing. It’s a grave sin against the Lord and His Commandment, thus sending the person to Hell if he dies unrepentant.
Better to err on the safe side and don't steal anything - even the smallest values. If we do commit such sin, then we must confess it as soon as we can make it to the Sacrament of Penance.