"When the church is tempted to take on board anything other than the simplicity of the Gospel and the sufficiency of Scripture, then it will always be in danger of capitulation and its missionary zeal will diminish.” —Alistair Begg
The Enlightenment brought "to light" a fresh store of wisdom that had been lost to the western world, but it also elevated reason over faith. Thus we must always use discernment when we interact with human insights.
All truth is God's truth and where we find that truth we can safely find agreement, but we must always read and listen with wisdom and understanding for secular thought is always a mixture of truth and error.
We must always examine the philosophical assumptions of humanistic thought for the flesh (human thought and effort) is “earthly and unspiritual" at best—it can only see “the things that can be seen." At worst, it can be demonic (1Timothy, 4:1; James 3:15). Though an element of truth may lie on the surface, the foundational presuppositions of secular movements are often at enmity with the gospel.
We can learn from secular sources, but we must compare all that we learn with the truth that we find in scripture. As I've written before, Christians are not avant garde. We do not "go on ahead" to hitherto unrevealed truth (2 John 1:3); we go back—back to "that which was from the beginning" (1 John 1:1), to that which Jesus and his apostles taught, the truth "once for all (time) delivered to the saints" (Jude 3).
The material is all that we need to lead lives of faith and obedience. As the Apostle Peter has written, God "has granted to us (the Apostles) all things that pertain to life and godliness…" (2 Peter 2:3). This is "the sufficiency of scripture."
We can and should learn from our culture, for we often find common grace and wisdom in human systems of thought, but we must never allow the insights of this world to correct or modify the plain statements of scripture.
message, the mission and the means (the spiritual dynamic and
governance) of the church are beyond the purview of natural men and
women. As Paul reminds us, "the natural person does not accept the
things of the Spirit of God, for they are folly to him. He is not able to understand them because they are spiritually discerned" (2 Corinthians 2:14).
Sola fide, sola gratia, sola scriptura (faith alone; grace alone; scripture alone). These "solae" are the foundation and framework of Christ's Church, the things without which nothing of eternal value can be done.