Since I am considering Orthodoxy from a Roman Catholic mindset, one thing I do not understand, fully at least, is the Orthodox not understanding sin in terms of mortal and venial. I will sum it up. My question is we all sin every day, but some sins seem clearly worse than others. The normal impatience common too us all is something we all struggle with. But a sin like fornication, murder, or stealing seems clearly worse. I think most Orthodox agree on this, and maybe it is the Catholic legalism here, but some distinction seems helpful. Mortal sins in Catholic theology are of course
1. Sins of grave matter
2. There is full consent of the will
3. There is knowledge that the sin was mortal, or at least a grave evil.
But how does Orthodoxy understand this, especially in light of going to the Eucharist. My Orthodox friends says some priests do not allow approaching the Eucharist without confession, whereas others it is a matter of decision of ones conscious. For example, not to be too personal, but I think it is a sin many single men struggle with. If I commit the sin of masturbation, I ask a Catholic will not approach the Eucharist without confessing it. The same goes for any other serious sin, like drunkeness.
The problem is we are all going to sin every day at least in a small way since "the just man sins seven times a day" (Proverbs 24:16). For example sadly I know I will likely get impatient tomorrow, have some murmuring thoughts within myself against others, and maybe even struggle with some impure thoughts about such and such a woman. As much as I want to not sin, I know I will at least lose my temper once.
How does the Orthodox approach this and how about when it comes to serious sins, like getting drunk or something. As as Catholic I consider getting drunk to be a serious sin. If it is done with full consent of the will and there it is no accident, there can be no excuse. Aquinas says that drunkeness is not a sin when the person does not know the strength or something like that, such as when Noah was gotten drunk in Scripture he gives as example. Forgive me because I am a Catholic trying to understand the Orthodox way, so I cite Aquinas and may look at sin in the more legal way that Catholics do. I am just looking for an answer.