The New testament.
Judaism and Christianity use it as a primary text. Islam and Bahai use it as a reference book. Chritianity combines it with the Gospel and calls it a Bible. Basically, any abrahamic religion uses it.
worshipers of chritianity are called christiansworshipers of chritianity are called christians
The holy book
Not all holy book are the same , the best holy book is the BIBLE
Holy book for Parsis or Zorastrianism is Avesta.
The holy book of Sikhs is Gurugranth Saheb.
There is not a secular holy book, that would be an oxymoron.
Yes. The holy book of Christianity is the Bible.
The Torah is the holy book of Judaism.
Quran is the Muslim holy book
Yes indeed the holy book of the Christians is the BIBLE.