“The Foundation of Communion with God” introduces readers to the Trinitarian piety of John Owen (1616–1683). Ryan McGraw’s introduction to Owen sketches the major events of this important theologian’s life and shows how his circumstances shaped his thought on the themes of the Trinity and public worship. The second part of the book presents forty-one brief selections from Owen’s writings that trace his thoughts on knowing God as triune, on Scripture and worship, on heavenly-mindedness, and on covenant and the church. Appendixes provide readers with a chronological list of Owen’s writings and a guide to them for those who wish to delve deeper into this great theologian’s thoughts.