The real challenge for Christian Apologetics is, first of all, to get beyond the problem of evil (the lynchpin of which is to be found in the doctrine of eternal conscious torment–especially as it is thought to apply to those who have never heard the Christian gospel); and second, to get beyond the problem of the authority of scripture (the lynchpin of which is to be found in the doctrine of Biblical inerrancy–especially in the absence of a single, authoritative interpretation or hermeneutic).
To my knowledge (and based on my own experience) the only way to begin to move beyond these two problems is by exploring the idea of the perennial philosophy. Fr. Richard Rohr offers a brief outline of this approach to the world’s wisdom traditions in the linked post, below. A more complete understanding can be gleaned from the writings of Aldous Huxley, Frithjof Schuon, and Huston Smith (see also this YouTube lecture by James Cutsinger).
What is lost if one takes this approach seriously? All that is lost is the extreme, dogmatic exclusivity that is so often attributed to Christianity by those who name the name of Christ (since, from the standpoint of the perennial philosophy, Christianity is one on-ramp among many to the universal Way of truth and life).
What is gained? 1) An understanding of– and compassion for –people of other faiths, and 2) a ready answer to those who question the truth of Christianity based, A) on the palpable injustice and absurdity involved (by any ordinary human standards) in the idea that those who were born under the curse of Adam’s sin and who have never heard the Christian gospel could or should suffer eternal conscious torment for not believing in Christ; and B) on the incoherence and demonstrable falsity of the teaching of Biblical inerrancy (to anyone who is not fully invested in maintaining the illusion of the emperor’s new clothes).
We need not disparage the Bible (since it contains an infallible message for those who have ears to hear); nor need we be particularly interested in the study other faiths (since the Christian tradition, rightly understood, offers all we need); but we must reject the fear and ignorance that undergirds the aforementioned doctrines (and which cannot fail to manifest, sooner or later, as fanaticism and intolerance toward those who think or believe otherwise). The idea of the perennial philosophy offers a good point of departure for those who are ready to exchange fear and fanaticism for a living faith in the living Word of God.