The origin of the Seventh-day Adventists (SDAs) can be traced to the Millerite Movement of the 19th Century. This movement was largely responsible for what has been called the Great Second Advent Awakening. William Miller (1782-1849) was a farmer who settled in upstate New York after the war of 1812. He was originally a Deist (a person who believes that God created the universe but has not been actively involved since). After two years of private Bible study, Miller converted to Christianity and became a Baptist lay leader. He was convinced that the Bible contained coded information about the end of the world and the Second Coming of Jesus. He also realized that he had an obligation to teach his findings to others. In 1831, he started to preach; the next year, he wrote articles. In 1833, he published a pamphlet on end-time prophecy. In 1836, his book Evidences From Scripture And History Of The Second Coming of Christ (1843) was published.

He expounded on Natural hygiene, raw food diets, water fasting, a vegetarianism diet, and an admonition to do no harm to other forms of life. We can see some of the same lifestyle today with the Seventh Day Adventists that was practiced by the Essenes 2,000 years ago.