Because Unitarians are not united by one creed, they do not follow the teachings of one religious book. Unitarians are free to live by any book (religious or not) or some live by no book.
I've recently donated THE TAO OF Willie Nelson to my local Unitarian library. It may be a strong contender...
Some of the most popular writers among Unitarians and Unitarian Universalists are Mary Oliver, Marge Piercy, Rumi, and Thich Nhat Hanh. The case could be made that a collection of their writings (and those of several others) could constitute a Unitarian/Unitarian Universalist holy book.
There isn't one, specifically. They are all-inclusive.
Christian Universalists use the Bible.
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.
Unitarian Universalism doesn't really have branches, it has been one religion since the 1960's.Another AnswerIf the question was, "What are the main branches of Universalism?"then the answer could be, Universal Reconciliation, Trinitarian Universalism, and Unitarian Universalism.
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
The last holy book of God is Qur'an; Muslim's holy book. Before Qur'an there are God holy books of Psalm, Torah, and the Bible.