Religion # of Followers Founded Holy Books/Texts Founder
Christianity 2.4 bil First Century Bible Jesus Christ
Islam 1.9 bil 600 AD
Qur’an, Hadith (sayings of the Prophet) and Sunna (descriptions of his
way of life.) Muhammad
Hinduism 1.2 bil Unknown, but at least 2000 BC The Vedas Unknown
Buddhism 0.5 bil Late 6th Century, BCE Tipitaka, Sutras, The Book of the Dead Siddhartha Gautama
Nonreligious/Agnostic/Atheist (see notes below) 450-500 mil
Sikhism 26 mil late 15th century the Adi Granth and the Dasam Granth Guru Nanak
Judaism 14.7 mil 1800 BCE the Tanakh Abraham
Taoism 9 mil 500 BCE Tao Te Ching (many authors including Zhuangzi) Lao Tzu (little evidence he existed)
Confucianism 6-7 mil 6th-5th century BCE The Analects disciples of Confucius, Mencius
Baha’i 5 mil mid 19th century The Kitab-i-Aqdas (the Most Holy Book) Baha’u’llah
Jainism 4.2 mil 6th century BCE
No one holy book, but many religious texts, the most well-known being
the Agam Sutras Nataputta Mahavira
Shinto 4 mil pre-6th century Kojiki (Records of Ancient Matters) along with the Nihon shoki No founder
Zoroastrianism 2.6 mil 6th century BCE Avesta Zarathustra (or Zoraster)
Atheist 450-500 mil (both)
The God Delusion (Richard Dawkins); The End of Faith (Sam Harris);
God Is Not Great (Christopher Hitchens); Breaking the Spell (Daniel
Dennett); The Four Horsemen ( a book on the New Atheism by all four
men)
Early thinkers: Epicurus, drawing from Democritus and the Atomists, Anaxagoras.
Later thinkers: Matthias Knutzen, German critic of religion, 1674. Ludwig Feuerbach,
Father of Modern Atheism (1800s). New Atheism: Richard Dawkins, Sam Harris,
Christopher Hitchens, Daniel Dennett and Auyaan Hirsi Ali (until her conversion to
Christianity in 2023).
Agnostic See above 1869
The Ethics of Belief (W.K. Clifford, 19th cent); Agnosticism and
Christianity and Other Essays (T.H. Huxley, 19th cent); A Treatise of
The Sophists and Socrates (not of Plato’s Republic), ‘agnosticism’ first coined in 1869
by T.H. Huxley, David Hume, Immanuel Kant, An Agnostic’s Apology and Other Essays