Glory in nothing but that you are in Christ In Finding Assurance with Thomas Goodwin, Andrew S. Ballitch explores how deeply the doctrine of assurance of faith impacted Goodwin's life and how Christians can learn from him today. Doubt is a common Christian experience, and assurance of faith is a universal Christian desire. The Puritans were acutely aware of this reality—none more than Thomas Goodwin (1600–1680). Goodwin wrestled with doubt for seven years after his conversion. When assurance came, it was with joy and confidence that Christ was for him personally. His confidence fueled a life of holiness, service, and perseverance. Ballitch highlights how Goodwin's life informed his theology and vice versa, so that readers can experience for themselves the joys of assurance.