The book with the Seven Seals was the compendium of Christian scripture produced in the time of the writing of Revelations. It consisted of the Septuagint (Old Testament), the four Gospels and two Epistles. The various sections were bound by a ribbon or seal, The totality was held together by the "Seventh Seal." The Book with Seven seals, then, is the Christian Bible.
I hope this doesn't dissapoint anyone!