What's the Book of Zephaniah All About?
Who Wrote the Book of Jonah and What's its Purpose?
What Does "the Dragon" in Revelation 12 Represent?
See PURGE; PURITY; UNCLEANNESS.
Orr, James, M.A., D.D. General Editor. "Entry for 'PURIFICATION'". "International Standard Bible Encyclopedia". 1915.