The Bible
Numbers 19
Directions are given for the sacrifice of a red heifer—The water of separation is used for purification from sin—Ceremonially unclean persons are sprinkled with the water of separation.
1And the Lord spake unto Moses and unto Aaron, saying,
11¶ He that toucheth the dead body of any man shall be unclean seven days.
15And every open vessel, which hath no covering bound upon it, is unclean.