One day, St. Anthony was in the Italian city of Rimini, where a good number of heretics lived. St. Anthony preached to them, hoping to win them over to Christ. But they did not care to listen to his words. So Anthony decided to go to the river near the sea. He stood on the bank between the river and the sea. Since the heretics had refused to pay attention to him, Anthony invited the fishes to come near and listen to the word of God.
Suddenly, a great number of large and small fishes came before him and, as they held their heads out of the water, they listened to his sermon. This they did peacefully and meekly. Then St. Anthony spoke in this way: “My brother and sister fishes, you must thank your Creator with much gratitude because he has given you such a noble element for your dwelling place, as well as many kinds of food to eat. He has given you fins also, so you can roam the waters as you like!”
Some of the fishes began to open their mouths and nod their heads as a way of praising God. On seeing this, St. Anthony rejoiced and cried out: “How blessed is the Creator! For the fishes give God more honor and praise than the heretics do. The fishes may lack the gift of reason, but these creatures of the sea pay more attention to the words of Anthony than do these faithless heretics.”