On Mondays, I answer questions frequently asked by those considering a return to the Catholic Church. How do I know this stuff? I was away for more than 30 years myself, and am the co-author of When They Come Home: Ways to Welcome Returning Catholics, a book for pastors and parish leaders interested in this ministry.
If I know I’m going to go home and do the same thing that I just confessed, what’s the point?
What’s the point, indeed?
If we’re talking about a venial sin, a slight to God, part of the process of reconciliation and penance is to recognize the flaw and work on ways to diminish or eradicate it. For example, if you are concerned about being short tempered with a loved one, the next 
step after reconciliation and penance is to come up with strategies to be more loving and perhaps a better listener.
If you’ve examined your conscience and are aware of conduct that is a “grave violation of God’s law” and intend to continue down that path, it’s not the time for this sacrament. That doesn’t make you any less Catholic—you are Catholic by virtue of your baptism—but if you are committing a mortal sin and intend to go on in that way, you should refrain from participating in the Eucharist until you are prepared to seek reconciliation.
In such situations, consider making an appointment with your pastor or another priest to discuss the matter. You also might want to read an authoritative text such as the Catechism to better understand the Church’s position, and whether your conduct truly is a mortal sin. Is it a serious matter? Do you understand its gravity? Are you freely continuing to commit the sin? And, perhaps the most important question—if you answer yes to all three of these questions, why are you persisting in this conduct? Are you truly serious about deepening your relationship with God through a return to the Church?
