Puritan Theology and the "Two Lights"

Back in November 2017 I did a review of Wallace Marshall’s Puritanism and Natural Theology (Pickwick, 2016) in which he argued for a robust natural theology in the Puritans and one foundational to their doctrine of supernatural theology. Marshall identifies natural theology for them as “all religious knowledge that is accessible through the use of reason independently of supernatural revelation.” Such an approach used rational (not rationalistic) arguments to “demonstrate the existence and attributes of God” to Christians with remaining unbelief, unbelievers in general, and skeptics (e.g. atheists) more narrowly. 
The Puritans in general regarded natural theology as sufficient for life unto God before the fall, after which time it still clearly though not savingly revealed God to alienated man. Thus, the written Word of God (the permanent record of special revelation) was necessary to overcome deficiencies of fallen reason regarding certain truths such as the Trinity and the essentials of the gospel. Interestingly, as seen in the Westminster Confession of Faith (1646), the Puritans employed natural theology to manifest or “abundantly evidence” (WCF 1.5) the Scriptures as special revelation, which were never received with “full persuasion and assurance” as divine truth apart from the work of the Holy Spirit. Likewise, “for the saving understanding of such things as are revealed in the Word” (WCF 1.7), the Puritans believed that “the inward illumination of the Spirit of God” was most necessary. 
The very first statement (1.1) of the Confession sums up Puritan views on natural and special revelation, the two “lights” I will address in this post: “Although the light of nature, and the works of creation and providence do so far manifest the goodness, wisdom, and power of God, as to leave men unexcusable; yet are they not sufficient to give that knowledge of God, and of his will, which is necessary unto salvation.” As a result of needing something more, the Lord revealed himself in special ways to his people (e.g. speech and acts) “and afterwards, for the better preserving and propagating of the truth, . . . to commit the same wholly unto writing: which maketh the Holy Scripture to be most necessary; those former ways of God's revealing his will unto his people being now ceased.” 
While the Confession begins with an emphasis on special revelation, it actually starts the discussion with natural revelation. The Westminster Larger Catechism (1647) gives what we could call an apt summary of this section in answer to the second question (which more explicitly focuses on natural revelation!), “How doth it appear that there is a God?”: “The very light of nature in man, and the works of God, declare plainly that there is a God; but his word and Spirit only do sufficiently and effectually reveal him unto men for their salvation.” Clearly, we can know God through the light of nature, but savingly only through the light of special revelation. 
We cannot be brought to a saving relationship with Christ apart from the Spirit revealing such to us by and with the Word. As summed up by John Owen (in his Exposition of Psalm 130, Works 6:428), we can “know God by the light of nature” but “cannot come to God by that knowledge.” Related to salvation, the light of special and supernatural revelation takes precedence over the light of nature. 
Stephen Charnock (1628–1680), most famous for his Discourses upon the Existence and Attributes of God (1682), stands as a representative of these views. In A Discourse of the Knowledge of God (Vol. 4 of The Complete Works of Stephen Charnock), for example, he speaks of natural knowledge (from natural revelation) as the ability to “know the being of a God, and something of his nature, helped by reason and discourse,” which can allow men to discourse “excellently of the nature of God.” 
Yet, there exists, according to Charnock, “no natural knowledge of Christ,” since such a “spiritual knowledge” is “discovered, not in the creatures, but in the Scripture.” It is “grounded upon a divine light, as plain and evident to the mind as any natural light is. Charnock takes care to distinguish spiritual knowledge of Christ from that which is merely “speculative,” residing in the head “without love in [the] will.” Such knowledge, possessed by even the devil, must not be confused with saving knowledge. However, the speculative provides the foundation to saving knowledge of Christ. Thus, “a speculative might be without a spiritual, yet a spiritual cannot be without a speculative.” 
Charnock argues for the necessary work of Spirit in attaining this spiritual knowledge. Indeed, we can get speculative knowledge of Christ “by the natural strength of the understanding,” but spiritual knowledge “is the effect of an infused faith and the Spirit’s operation.”  The speculative “knows God in the Scripture by reading,” the spiritual “by relish.”
Charnock rightly sees that the Word must reach the heart and not simply the head, it is not enough to possess “a floating knowledge in the head, but a knowledge sinking to the heart.” We do well to focus on the same in our ministry to others and, in connection with it, Charnock’s fitting reflection: “The thinking of God and Christ with the head, and embracing Christ with the heart, are two distinct things.”
Bob McKelvey