OK, first we need to establish the fact that there are a lot of different types of sin. The Bible, as well as our catechism, is filled with examples of how we sin (as is television!) The Catechism of the Catholic Church sums it all up nicely in section 1853:

Sins can be distinguished according to their objects, as can every human act; or according to the virtues they oppose, by excess or defect; or according to the commandments they violate. They can also be classed according to whether they concern God, neighbor, or oneself; they can be divided into spiritual and carnal sins, or again as sins in thought, word, deed, or omission. The root of sin is in the heart of man, in his free will, according to the teaching of the Lord: “For out of the heart come evil thoughts, murder, adultery, fornication, theft, false witness, slander. These are what defile a man.” But in the heart also resides charity, the source of the good and pure works, which sin wounds.

That’s a pretty helpful summary. Through it, we see that sin can be classified by what it attacks and how and why it attacks the good. We can sin by doing something; we can sin by not doing something. The catechism makes clear that our hearts are the problem, as is our abuse of free will. The cool thing is, and this is classic God, the heart is a place where hope is – as Jesus, who redeemed us, lives there.

Now, in general, all sins fall into one of two categories: mortal and venial. What is the difference? The difference tends to be manifested most clearly in the consequences of our actions (or inaction)!

When we commit a mortal sin, we damage our soul in a very specific way: We wound our hearts’ ability to repent and receive mercy. The damage we do is real and intense, and the catechism tells us that it takes a special initiative of mercy on God’s part to heal us. (1856)

So, what are the mortal sins? Well, it’s easier to describe how a mortal sin is committed than what specific sins are mortal. Here is an easy way to remember it: C.I.A.

That acronym works like this:

C – Circumstance: We have to be completely free to choose to sin or not.

I – Intent: We have to know that it is a sin, be free not  to do it and do it anyway.

A – Action: The sin needs to be of a serious matter.

If we commit a sin and all three of these things are simultaneously true, then we have committed a mortal sin. The consequences are that we should not receive Communion without either going to confession or making sure that we are going to go to confession as soon as possible.

So, then, what is venial sin? Venial sin is, simply, all the rest. Venial sins are those sins that damage our hearts and souls, but still allow God’s love to live and work within us. The danger of venial sins is that they are a choice we make toward something less than God and what he wants for us. According to the catechism, venial sins also have the ability to condition us to commit a mortal sin. You know how it goes, the more we sin, the more open we are to sinning and the more difficult it is to recognize the sin and repent.

I hope this is helpful; the key to all of this is to remember the power and consistency of God’s mercy. There is nothing we can do that God can’t forgive; we need to remember to ask.

Enjoy another day in God’s presence.