[1] Adler thinks that the term "natural theology" is a misnomer and is actually apologetics, and cites as an example Thomas Aquinas' Summa Contra Gentiles, addressed to the Jews and Moors in Spain.
Justin Martyr looked at people like Heraclitus and Socrates as possessing the divine light of revelation and believed them to be true philosophers.
[6] The disciplines of Philosophy and Theology have often been connected, with theologians and philosophers interacting and debating similar and sometimes overlapping issues.
Thomas Aquinas, one of the most influential philosophers and theologians in history, for instance, borrowed much of his concepts from Aristotle.
Scholasticism dominated both the philosophical and theological landscape in the Middle Ages, with theologians such as Aquinas, Anselm of Canterbury, Duns Scotus, William of Ockham, Peter Abelard, Bonaventure, and Albertus Magnus playing key roles in both philosophy and theology.
[6] In modern times, Anthony Thiselton has shown in his Fusion of Horizons the role that philosophy has played in the interpretation of scriptures, i.e., in the field of hermeneutics.
There are others, like Sadhu Sundar Singh, for instance, who believe that it is the illumination of the Holy Spirit that gives the truest meaning of revelation.
Yet, one can't fail to see that cultural grids play an important role in the development of theology.
In recent decades, some of the most well-known philosophers who have written from a Christian perspective are Alvin Plantinga, Alasdair MacIntyre, William Lane Craig, Jean-Luc Marion, Paul Tillich, Charles Taylor, Richard Swinburne, and James K. A. Smith.
Some existentialistic or neo-orthodox Protestant intellectuals like the Swiss Reformed theologian Karl Barth turned away from philosophy (called fideism) and argued that faith should be based strictly upon divine revelation.
One task of philosophical theologians is to attempt to reconcile certain aspects of Christian doctrine with developments in philosophy.