People eat fish on Good Friday primarily due to a Christian tradition of abstaining from eating meat on this day to commemorate the crucifixion of Jesus Christ. Historically, the Catholic Church decreed that meat from warm- blooded animals should be avoided as a form of penance and sacrifice. Fish, being cold-blooded, was allowed and thus became the preferred alternative. Additionally, fish hold symbolic significance in Christianity, as many of Jesus' disciples were fishermen, and fish were used as a secret symbol among early Christians. This tradition has carried on culturally, with many people eating fish or fish dishes on Good Friday as a mark of respect and remembrance of Christ's sacrifice.