How do I explain why Catholics pray for the dead?

My priest has urged me to have a private mass for my protestant father who committed suicide (medical issues contributed to). I am open to that and would like to invite my protestant family members but feel I need to explain the reason we are doing the mass. How do I explain the what we believe?

These links should be helpful for understanding the Roman Catholic Church’s teachings on the particular and final judgment and praying for the dead. If you have any further questions or concerns that are not answered by these links, please contact Catholic Answers directly.

Recommended Reading:
Why do we pray for souls in purgatory?

If the souls in purgatory are destined for heaven, why do we pray for them?
He will come again to judge the living…

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