Traditionally speaking, Friday is a day of penance and so Catholics practice abstinence, and some may even practice fasting, although it is not obligatory.
The purpose of penance is to atone for our sins and for the sins of the Church and the world.
It is also for the conversion of sinners, as well as for our own ongoing conversion.
With all that said, then penance is to be seen not just for ourselves but for others as well.
In the 1st reading, St. Paul talks about the extent of the penance he was willing to do for the conversion of his people.
His sorrow is so great, his mental anguish so endless, that he would willingly be condemned and be cut off from Christ if it could his people.
If that is what St. Paul was willing to do for the conversion of his people, then we may want to take a serious look at our understanding of penance and how we are doing it.
Besides doing penance for our good, penance is also our Christian duty for others.
God loves a humble and contrite heart. God also loves a heart that is willing to do penance for the good of others.
Just as Jesus sacrificed Himself on the Cross to save us, may our penance also bring about blessings on ourselves and on others.