Books include: The Hebrew Gospel and the Development of the Synoptic Tradition (Eerdmans, 2009); Is Jesus the Only Savior? (Eerdmans, 2005); The Divine Intruder (NavPress, 2000).

Commentaries include: commentary on Hebrews in Renovare Study Bible (Harper, 2005); commentary on Romans in New Interpreter's Study Bible (Abingdon, 2003); commentary on The Gospel of Mark, PNTC (Eerdmans, 2002); commentary on Romans, NIBC (Hendrickson's 1992).

Also publishes numerous articles in scholarly and popular journals, and is a frequent speaker at churches, conferences, and lectureships.

Member of the Center of Theological Inquiry, Princeton, N.J. (2007). Recipient of several teaching awards, including Outstanding Professor at Jamestown College and Whitworth University; former scholar for North Dakota Humanities Council; recipient of Templeton Grant in Science and Religion (1996); recipient of Deutsche Akademische Austausch Dienst Award (1993).

Leader of study programs to Luther's Germany; church struggle in Germany; ancient Christian sites in Turkey; historical geography of Israel and Palestine.

Ordained minister, PCUSA. Contributing editor of Christianity Today. Climbed the Mittellegi Ridge of the Eiger in 2003.