Craig became a Christian believer in high school at the age of 16. His vocation and academic studies reflect his religious commitment to Christian beliefs within the Protestant Evangelical tradition.
In theological commitments he holds to an Arminian (specifically, Molinist) view concerning the grace of God and the role of the human will in conversion. He has had friendly connections with para-church ministries such as Campus Crusade for Christ and Christian International Ministries (Europe).
In his early reading and studies, Craig was influenced by the writings of Francis Schaeffer and Edward John Carnell. He studied philosophy under Stuart Hackett.