George Edward Day was born on March 19, 1815, in Pittsfield, Berkshire, Massachusetts.

He was a clergyman, professor, and author. In 1838, he graduated from Yale Theological Seminary and became an assistant instructor there until 1840. From 1840 to 1851 he served as a Congregational pastor in Marlboro and Northampton, Mass. From 1851 to 1866, he was a professor of biblical literature in Lane Theological Seminary in Cincinnati, Ohio where he founded the General Theological Religious Library. Then he was appointed professor of the Hebrew language, literature, and biblical theology at the Yale Theological Seminary. While at Yale he founded The Theological Eclectic and served as its editor (1863-1871). He also served as a librarian both at Lane and Yale. He was a contributor to Smith's "Bible Dictionary" and published numerous articles in various periodicals.

In 1843, he married Amelia Hotchkiss (1821–1875) and in 1876, he remarried Olivia Clark Hotchkiss (1824–1909). He died on July 2, 1905, in New Haven, Connecticut.