How do you speak with a priest in Confession when you do a devotional confession and he says that you don’t need to mention past sins as they are already forgiven?
I assume that you mean by “devotional confession” going to confession even if you have no mortal sins on your conscience. Many spiritual writers will refer to that as “frequent confession,” since it is still a sacramental encounter, not just a private act of devotional piety.
In general, if you explain to the priest the situation you are in, he will be able to adjust his guidance. If he doesn’t know that this is a “devotional” confession, he may be concerned that you are 
being over-scrupulous by mentioning imperfections or not fully willed venial sins. In that case, he may try to comfort you by explaining the difference between sins of malice and sins of weakness, or other distinctions. But if you explain that you – for example – have a spiritual director and are following a spiritual program, he will understand that you are making a good confession and working intentionally on spiritual progress. In that case, he won’t think you are falling into being over-scrupulous.
On the other hand, if you mean by “devotional confession” a “general confession,” where you confess all the sins of your past life or even of an extended period (the last year, for example), then it’s important to mention that to the priest at the beginning of your confession. In a general confession like that, it is common to mention sins that we have already confessed, as a way of stirring up a sincere spirit of contrition. A general confession of this sort is often part of a spiritual retreat and aids the retreatant in entering more deeply into God’s mercy and love. Making that kind of examination of conscience can even help us identify behavior patterns that shed light on the roots of our common sins and faults. But if the priest you are confessing to doesn’t know you are doing a general confession, he may think you are just being over-scrupulous and advise you to focus only on the period since your last confession.
If, on the other hand, you feel moved to confess over and over again sins that you have already confessed, even outside the context of a general confession, this could be a good topic to discuss in spiritual direction. Even in confession, you could ask the priest about it. You could explain that you know it is not necessary to “re-confess” your sins, but even so you are feeling a desire and a need to confess them again. That could spark a beautiful dialogue – maybe the Lord is saying something to you through that desire, maybe there is something for you to discover there.
I hope these thoughts have been helpful.
God bless you! Fr John
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Art for this post on what to tell a priest in a devotional confession: Interior Scene [Confession], Jean Alphonse Roehn (1799-1864), unknown date, PD-US author’s life plus 100 years or less, PD-Worldwide, Wikimedia Commons.
