Matthew 18:6

But whoever shall cause one of these little ones that believe in me to fall away, it were better for him to have a great millstone hung round his neck, and be swallowed up in the depth of the sea.

Revelation 18:21

And a strong angel took up a stone like a great millstone, and cast it into the sea, saying, Thus with violence shall Babylon the great city be thrown down, and shall never more be found.

Treasury of Scripture Knowledge

Summary

The depths have covered them: they sank into the bottom as a stone.

Depths

Bible References

Depths

Matthew 18:6
But whoever shall cause one of these little ones that believe in me to fall away, it were better for him to have a great millstone hung round his neck, and be swallowed up in the depth of the sea.

They

Revelation 18:21
And a strong angel took up a stone like a great millstone, and cast it into the sea, saying, Thus with violence shall Babylon the great city be thrown down, and shall never more be found.