Isaac Ambrose (May 1604 – January 23, 1664) was an English preacher and Puritan divine whose calling from God within the Presbyterian tradition enriched spiritual life through preaching and writing across the mid-17th century. Born in Ormskirk, Lancashire, England, to Richard Ambrose, vicar of St Mary’s Church, and an unnamed mother from a yeoman family, he was baptized on May 17, 1604, the youngest of several children. Educated at Brasenose College, Oxford, he graduated with a B.A. in 1624, entered the ministry in 1627, and later earned a B.D., reflecting his scholarly bent despite lacking formal ordination records. Ambrose’s calling from God led him to serve as curate at St Edmund’s Church in Castleton, Derbyshire (1627–1631), then as one of the King’s four preachers in Lancashire from 1631, based at St Mary’s Church in Garstang until 1642, when Civil War unrest prompted his move to Preston and later Leeds. His sermons, marked by a meditative piety and call to holiness, were delivered amidst persecution—he was ejected from Garstang in 1662 for Nonconformity—yet he continued preaching until his death. A prolific writer, he authored Prima, Media, et Ultima (1650), a trilogy on regeneration, sanctification, and heaven, alongside Looking Unto Jesus (1658), urging believers to fix their eyes on Christ. Married twice—first to Judith in the 1630s, with children including Hannah, then to a second wife after Judith’s death around 1652—he passed away at age 59 in Preston, Lancashire, buried at St Wilfrid’s Church.