Jeremiah 51:63 Talmud References

וְהָיָה֙ כְּכַלֹּ֣תְךָ֔ לִקְרֹ֖א אֶת־הַסֵּ֣פֶר הַזֶּ֑ה תִּקְשֹׁ֤ר עָלָיו֙ אֶ֔בֶן וְהִשְׁלַכְתּ֖וֹ אֶל־תּ֥וֹךְ פְּרָֽת׃

And it shall be, when thou hast made an end of reading this book, that thou shalt bind a stone to it, and cast it into the midst of the Euphrates;