"Mental Pictures: Shapes and Colors in the Thought of G. K. Chesterton,"Inklings Forever, vol. vii, Taylor University, 2010
"C. S. Lewis on Friendship,"Inklings Forever, vol. vi, Taylor University, 2008
"Trinity and Spirituality: An Historical Typology," Trinity Forum Academy, 2007
"God," Dictionary of Mission Theology, Inter-Varsity Press, 2007
"Jesus, the True and Living Way," Doon Theological Journal, vol. 3, no. 2, July, 2006
"Jesus, the True and Living Way," Midwest Evangelical Theological Society, 2006
"Choices along Life's Journey: The Intersection of Time and Eternity in The Great Divorce," The Lamp Post, vol. 29, no. 2, Summer, 2005
Coeditor with Paul Johnson of Collected Works of G.K. Chesterton, vol. xvii comprising Chesterton's studies of William Blake, William Cobbett, G.F. Watts and Robert Browning, Ignatius Press, publication date not determined.
"La formación espiritual de Lutero," Congreso de Espiritualidad, Seminario ESEPA, 2004
"Liturgical and Ascetic Fasting: An Important Difference in the History of the Church," Doon Theological Journal, vol. 1, no. 2, July, 2004
"Fasting: The Discipline for the In-Between Time," Doon Theological Journal, vol. 1, no.1, January, 2004
"Biblical Stewardship," Niyog, 2004
"La perspectiva bíblica de las religiones," Congreso de Misiones, Seminario ESEPA, 2003
"Choices along Life's Journey: The Intersection of Time and Eternity in The Great Divorce," C.S. Lewis Summer Institute, Cambridge University, 2002
"The Imitation of Christ: Pattern for Discipleship and Mission," Conference: To Know God, Dallas Seminary, 2001
"Cambio de paradigmas en la historia de la iglesia: Reenfocando la misión generacionalmente," Fraternidad Teológica Latinoamericana, 2001
"A Missionary Spirituality," Missiology, vol. xxvii, no. 3, July, 1999
"El paradigma de la historia redentora," Fraternidad Teológica Latinoamericana, 1997
"Henry Ward Beecher," "Cadle Tabernacle," and "Second Presbyterian Church," Encyclopedia of Indianapolis, Indiana University Press, 1994
"Knowledge and Mystery in G.K. Chesterton's The Man Who Was Thursday," Christianity and Literature, Winter, 1993
"St. Antony and the Demons: A New Interpretation of the Monastic 'Flight into the Desert'," Midwest Evangelical Theological Society, 1993
"Chesterton and Lewis on Romance and Joy," The Bulletin of the New York C.S. Lewis Society, vol. xxii, no. 2, December, 1990
"A literatura do amor e o amor de Deus," Conference of G.B.U. Portugal, 1988
"The Adventure of Life: Romance in the Writings of G.K. Chesterton," doctoral dissertation, Drew University, 1986
"G.K. Chesterton and the Romance Tradition: Scott and Stevenson," Modern Language Association, 1984