Recommended reading: G.K. Chesterton, Theologian by Fr. Aidan Nichols.
"Chesterton, one of the great converts of the twentieth century, draws us directly into an encounter with the Word of God, showing us the faith of the Church as most of us have never seen it before. Fr. Nichols has gathered the most powerful theological passages from the many works of Chesterton, and included his own concise explanations of the keen and sometimes surprising ways they illuminate the most profound questions ever asked by man."