Joshua 4:6 YLT

⁴  And Joshua calleth unto the twelve men whom he prepared out of the sons of Israel, one man -- one man out of a tribe;

⁵  and Joshua saith to them, 'Pass over before the ark of Jehovah your God unto the midst of the Jordan and lift up for you each, one stone on his shoulder, according to the number of the tribes of the sons of Israel,

⁶  so that this is a sign in your midst, when your children ask hereafter, saying, What 'are' these stones to you?

⁷  that ye have said to them, Because the waters of the Jordan were cut off, at the presence of the ark of the covenant of Jehovah; in its passing over into the Jordan were the waters of the Jordan cut off; and these stones have been for a memorial to the sons of Israel -- to the age.'

⁸  And the sons of Israel do so as Joshua commanded, and take up twelve stones out of the midst of the Jordan, as Jehovah hath spoken unto Joshua, according to the number of the tribes of the sons of Israel, and remove them over with them unto the lodging-place, and place them there,