Many people ask why Catholics are permitted to eat fish on days of abstinence ("Fish Fridays"!), but not meat. After all, isn't fish a kind of "flesh"?
The traditional Catholic allowance for fish on days of abstinence has a mystical relationship to the episode of the Great Flood of Noah, in which it rained forty days and forty night - just as Lent is a forty day period of universal cleansing. During this time, Noah and his family ate fish, since they were not permitted to eat the animals on board the ark. Moreover, the fish were preserved in the Great Flood (fish can swim), but land animals were not (they drowned). Hence, fish also play a part in the ministry, parables, and teaching of Christ - after all, many of the Apostles were once fishermen.
However, Saint Thomas Aquinas provides us with a more practical reason for why meat is not allowed, but fish are permitted:
I answer that, fasting was instituted by the Church in order to bridle the concupiscences [i.e. inordinate desires] of the flesh, which regard pleasures of touch in connection with food and sex. Wherefore the Church forbade those who fast to partake of those foods which both afford most pleasure to the palate, and besides are a very great incentive to lust.Are there any nutritionists out there who can confirm this? Any comments?
Such are the flesh of animals that take their rest on the earth, and of those that breathe the air and their products, such as milk from those that walk on the earth, and eggs from birds [here is the traditional prohibition against eggs, milk, and cheese since they all come from land animals]. For, since such like animals are more like man in body, they afford greater pleasure as food, and greater nourishment to the human body, so that from their consumption there results a greater surplus available for seminal matter, which when abundant becomes a great incentive to lust. Hence the Church has bidden those who fast to abstain especially from these foods. (Summa theologiae II-II q. 147, a. 8)
You may also enjoy reading:
- The Mystical Significance of the Fish in Jonah
- Why 153 Fish in John's Gospel? The Jewish Answer
- Fishers of Men and the 153 Fish in John 21:11