The document discusses the origins and early history of the Adventist movement. It describes several key figures like William Miller who predicted Jesus' return around 1843 and began preaching in 1831. After the "Great Disappointment" of 1844 when Jesus did not return, individuals like Hiram Edson had insights that led to establishing the doctrine of the heavenly sanctuary and keeping the Sabbath on Saturday. Joseph Bates was influential in teaching that the Sabbath should be observed on the seventh day.