Mr. Nivelo does not understand Hebrew, but the shock of a fish speaking any language, he said, forced him against the wall and down to the slimy wooden packing crates that cover the floor.
He looked around to see if the voice had come from the slop sink, the other room or the shop's cat. Then he ran into the front of the store screaming, ''The fish is talking!'' and pulled Mr. Rosen away from the phone.
''I screamed, 'It's the devil! The devil is here!' '' he recalled. ''But Zalmen said to me, 'You crazy, you a meshugeneh.' ''
But Mr. Rosen said that when he approached the fish he heard it uttering warnings and commands in Hebrew.
''It said 'Tzaruch shemirah' and 'Hasof bah,' '' he said, ''which essentially means that everyone needs to account for themselves because the end is near.''
The fish commanded Mr. Rosen to pray and to study the Torah and identified itself as the soul of a local Hasidic man who died last year, childless. The man often bought carp at the shop for the Sabbath meals of poorer village residents.
Mr. Rosen panicked and tried to kill the fish with a machete-size knife. But the fish bucked so wildly that Mr. Rosen wound up cutting his own thumb and was taken to the hospital by ambulance. The fish flopped off the counter and back into the carp box and was butchered by Mr. Nivelo and sold.