New Revised Standard Version
When you finish reading this scroll, tie a stone to it, and throw it into the middle of the Euphrates,

Contemporary English Version
When you finish praying, tie the scroll to a rock and throw it in the Euphrates River. Then say,

New American Bible
When you have finished reading this scroll, tie a stone to it and throw it into the Euphrates,

Douay-Rheims Bible
And when thou shalt have made an end of reading this book, thou shalt tie a stone to it, and shalt throw it into the midst of the Euphrates:

And when thou shalt have made an end of reading this book, thou shalt tie a stone to it, and shalt throw it into the midst of the Euphrates:

Revelation 18:21 And a mighty angel took up a stone, as it were a great millstone, and cast it into the sea, saying: With such violence as this, shall Babylon, that great city, be thrown down and shall be found no more at all.

to denote the utter ruin of mystical Babylon

Jeremiah 19:10,11 And thou shalt break the bottle in the sight of the men that shall go with thee. . . .

Revelation 18:21 And a mighty angel took up a stone, as it were a great millstone, and cast it into the sea, saying: With such violence as this, shall Babylon, that great city, be thrown down and shall be found no more at all.