John Preston (1587–1628) was a Reformed English theologian and preacher. He was dean of Queens College, Cambridge, master of Emmanuel College, Cambridge, regular preacher at Lincoln’s Inn, and chaplain to the King. His Wikipedia entry seems accurate enough. James T. O’Brien has published an edition of this brief, edifying work in modern English and made it available briefly at no cost on Amazon (HT: Nick Batzig for the heads up).
If you want to know more about John Preston I recommend Paul Schaefer’s excellent work, The Spiritual Brotherhood: Cambridge Puritans and the Nature of Christian Piety. Jonathan D. Moore has published a volume on Preston’s doctrine of the atonement and the development of Reformed theology in the period: English Hypothetical Universalism: John Preston and the Softening of Reformed Theology. This is on my ever-growing shelf of books to finish.