Joshua 24:27

And Joshua said unto all the people, Behold, this stone shall be a witness, a monument and memorial, unto us; for it hath heard all the words of the Lord which He spake unto us, during the meeting which had gone before; it shall be therefore a witness unto you, lest ye deny your God, it would always serve to remind them of their solemn promise, lest they deny Jehovah by thought, word, or deed.