The Church abolished most of the norms regulating "meatless Fridays" and declared Fridays outside of Lent merely as "A Day of Penance." Does the penance have to be performed on Friday and are there any parameters to observe?
Generally, the penance should be performed on Friday, though exceptions can be made due to other obligations such as attending family or civic celebrations. Strictly speaking, one can work out deferrals or dispensations in regard to Friday observances with their pastor, but practically, most simply work through this on their own.
The thinking back in the 1970s when “meatless Fridays” were substituted with a day of penance was to offer other observances to people on Friday. Simply giving up meat and going to Red Lobster was hardly a penance for most, though the law was being observed technically. Hence it was thought to permit any range of penances, from giving up other things, to taking on special prayers or works of charity.
But as your question implies, it is difficult to follow an uncertain trumpet, and many Catholics simply drifted from any Friday observance with such wide-open parameters. Psychologically it would seem that having a clear focus is necessary to assist in such practices. Hence, some Bishop’s conferences are going back to meatless Fridays.
Here in America, that is not the case, though there has been some discussion. For now, you are largely free to determine how to observe Friday, presuming it has a penitential character. It could be to abstain from something good, or to take on some pious or charitable work.
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