The Jews practiced Tishlikh (tish-lick) on Yom Kippur the Day of Atonement.
They would cast bread (sin) upon the sea and watch for the fish to eat it and take it away.
Perhaps that is what Peter was implying, that Jesus as the Bread of Life, who takes away our sins as we “cast our cares upon Him.”
Maybe that is where the expression “cast your cares upon the waters” comes from. Interesting.
