[quote="nickybr38, post:17, topic:272256"]
That's very nice but what IS grave matter? :) That's why the Catechism didn't help me much. It didn't specify which sins constitute grave matter... Yes it's nice to know I am not committing mortal sin because I was not aware something was grave matter but isn't my obligation to learn? And to know?
Yes to form conscience :)
One can go through the 10 commandments section ...(much mentioned there is grave matter. At times it even emphasizes that something is grave by stating it. One can see by context often too. But yes I understand that one needs other sources as well ...the CCC is not meant to be exhaustive...one can use something like the examine that CA sells that I noted above.
1858 Grave matter is specified by the Ten Commandments, corresponding to the answer of Jesus to the rich young man: "Do not kill, Do not commit adultery, Do not steal, Do not bear false witness, Do not defraud, Honor your father and your mother."132 The gravity of sins is more or less great: murder is graver than theft. One must also take into account who is wronged: violence against parents is in itself graver than violence against a stranger.
The obligation of the Decalogue
2072 Since they express man's fundamental duties towards God and towards his neighbor, the Ten Commandments reveal, in their primordial content, grave obligations. They are fundamentally immutable, and they oblige always and everywhere. No one can dispense from them. The Ten Commandments are engraved by God in the human heart.
2073 Obedience to the Commandments also implies obligations in matter which is, in itself, light. Thus abusive language is forbidden by the fifth commandment, but would be a grave offense only as a result of circumstances or the offender's intention.
2268 The fifth commandment forbids direct and intentional killing as gravely sinful. The murderer and those who cooperate voluntarily in murder commit a sin that cries out to heaven for vengeance.69
Infanticide,70 fratricide, parricide, and the murder of a spouse are especially grave crimes by reason of the natural bonds which they break. Concern for eugenics or public health cannot justify any murder, even if commanded by public authority.
2484 The gravity of a lie is measured against the nature of the truth it deforms, the circumstances, the intentions of the one who lies, and the harm suffered by its victims. If a lie in itself only constitutes a venial sin, it becomes mortal when it does grave injury to the virtues of justice and charity.
2181 The Sunday Eucharist is the foundation and confirmation of all Christian practice. For this reason the faithful are obliged to participate in the Eucharist on days of obligation, unless excused for a serious reason (for example, illness, the care of infants) or dispensed by their own pastor.119 Those who deliberately fail in this obligation commit a grave sin.