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If you fail to plan, you plan to fail. ~ Weight Watchers (I know!)
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Consider that in ages past, meat was a luxury. Meat carries with it the connotation of celebration and indulgence. Only in rich modern times has this notion faded. (Think Golden Arches...)
Also, one can consider that the fish, in ancient times, was (and remains) a symbol for Christ. Eating fish was a symbolic way of associating one's self with Christ in a Eucharistic sense.
At a time during the Roman Empire when Chrisitanity was illegal and Christians were put to death for practicing their faith, worship had to be held in secret places. A fish painted on the outside door of a house let Christians know that worship would be held inside.
Ever since, a fish has been one of the many symbols to remind Christians of Jesus. ~ notes from my RCIA manual.
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