[annalex]

Mortal sin is an act, inaction, speech, or thought done knowing that it offends God with full cooperation of the will. As Wikipedia puts it,

In all Catholic moral theology, a mortal sin, as distinct from a venial sin, must meet all of the following conditions:

• its subject must be a grave (or serious) matter;
• it must be committed with full knowledge, both of the sin and of the gravity of the offense;
• it must be committed with deliberate and complete consent.

  (Mortal sin)

When ther is an offense but it is insignificant, or unintended, or done out of ignorance, then the sin is venial.

Human physiology provides plenty of examples of venial sin. Unintended exposure to nudity, for example, leads to arousal which is morally neutral, -- it simply indicates one has a healthy libido. Lustful thoughts entertained following the arousal might be hard to control, that is venial sin. Taking a decision to seek out more of such scenes in order to experience more lustful thoughts becomes mortal sin, because now a decision has been freely made.

[hosepipe]

I wonder if dividing sin into category's defeats the purpose of the concept and is itself a sin?..
Since you MUST be perfect as you're father in heaven is perfect.. as it is written..
Perfection allows ZERO sin..

You know, prevarication of the ministry of Christ..

[MarkBsnr]

I just reread your post.

Oh well, I need to go to confession sometime soon, anyway.