Joshua 4:1-3

And it came to pass, when all the people were clean passed over Jordan, that the LORD spake unto Joshua, saying, Take you twelve men out of the people, out of every tribe a man, And command ye them, saying, Take you hence out of the midst of Jordan, out of the place where the priests' feet stood firm, twelve stones, and ye shall carry them over with you, and leave them in the lodging place, where ye shall lodge this night.