Firmin, Giles an English Nonconformist divine, was born in Suffolk in 1617, and educated at Cambridge. He was ordained, and became minister at Shalford, in Essex, where he continued until he was ejected, in 1662, by the act of uniformity. He died in 1697, leaving several sermons and theological treatises (1652 sq.), the best of which is The Real Christian. See Chalmers, Biog. Dict. s.v.; Allibone, Dict. of Brit. and Amer. Authors, s.v.