Mortal Sins and Venial Sins.....Explain?


What are the mortal sins and what are venial sins??? I know the former is the bad one and the venial sins aren’t as bad but what comes under the catergory of each heading??? And is seeking forgiveness for a mortal sin harder than for a venial sin or will sincerely confess to the Lord and asking forgiveness sufficient for both???


Venial sin is accidental sin. Like when someone cuts you off in traffic and you blurt out “You *#^%!”. It is certainly not honoring to God and neither is it a peaceful thing to do, but you also did not plan it out before hand and did not knowingly act in violation of your conscience and therefore the sin is not mortal but rather venial.

Mortal sin is when you deliberately and with full knowledge of what you are doing commit serious sin. I don’t think grabbing a cookie from the cookie jar is necessarily a mortal sin, even if it was premeditated. However, if you commit serious sin (the Decalogue is a pretty good list) and do so in full knowledge of what you are doing and you commit the sin meaning to sin then you have committed mortal sin.

The difference between the two is that mortal sin separates us from the grace of God given at baptism and if you were to die with unrepented unabsolved mortal sin then you would go to Hell.

The only normal way to be forgiven of sin is the Sacrament of Penance. When you confess and do your act of contrition, even if it is imperfect, the authority given to St. Peter and passed on to the Bishops and extended to this day is such that when the Priest absolves you your sin is forgiven.

This does not mean that God is not free to forgive sin however He chooses best; it does mean that the only normal method given to the Church by God is by confession, repentance and absolution.


“Mortal sin destroys charity in the heart of man by a grave violation of God’s law; it turns man away from God, who is his ultimate end and his beatitude, by preferring an inferior good to him.” from the Catechism para 1855.

Mortal sin must meet 3 criteria:

  1. be of grave matter (breaking one of the commandments, etc)
  2. committed with full knowledge (you know it’s a grave sin)
  3. committed with deliberate consent (knowing it’s a grave sin, you do it anyway)

“Venial sin weakens charity; it manifests a disordered affection for created goods; it impedes the soul’s progress in the exercise of the virtues and the practice of the moral good; it merits temporal punishment. Deliberate and unrepented venial sin disposes us little by little to commit mortal sin. However venial sin does not break the covenant with God. With God’s grace it is humanly reparable.” from the Catechism para 1863.

Mortal sins must be confessed to a Priest at confession.


From what i have studied, A mortal sin is a deliberate act.
You have thought hard about it. You know what you are about to do is wrong. Then you decide to do at of your own free will.

If you did not put a lot of thought in it. Or if you didn’t know what you were doing was wrong. Or if a mental imparement, or coursion. Or not of you own free will than it is not Mortal.



tietjen is right on the money! as a p.s. remember, sin is in the will, we cannot commit a sin by accident.

God bless,



You can read in the Catechism regarding mortal and venial sin and the difference between them.

Confer with your priest if you are unsure whether a sin is mortal or venial.


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