"For God, who commanded the light to shine out of darkness, has shined in our hearts, to give the light of the knowledge of the glory of God in the face of Jesus Christ." 2 Corinthians 4:6
When a man is walking in the darkness and death of unregeneracy, he has no true light. He may indeed have a false light, as the light of presumption, delusion, or vain-confidence; but all such borrowed light is worse than darkness; as the Lord says, "If the light that is in you be darkness, how great is that darkness!"
The only saving light is the light of God shining into the soul, giving us to see and know "the only true God, and Jesus Christ whom he has sent." A man may have the clearest light in his judgment, and yet never have the penetrating light of the Spirit producing conviction in his soul; he may have the soundest knowledge of the doctrines of grace, and see the harmonious scheme of salvation; and yet never have seen a holy God by divine teaching, nor have ever felt the spirituality of God's righteous law condemning him as a transgressor. But "the light of life," as the Lord calls it, is sure to guide its possessor aright. If we have it not, we shall be sure to go astray; we shall be entangled in some error, plunge into some heresy, imbibe some doctrine of devils, drink into some dreadful delusion, or fall into some dreadful sin, and "concerning faith make shipwreck."
A false light is something like the lights which pirates hold up to entrap ships to their destruction; or like the fires, which the "wreckers," those dreadful characters in Cornwall, used to kindle on their iron-bound coast, in order that the mariner might mistake them for some friendly light-house, and run his vessel on the rocks, where those heartless wretches plundered it. A false light can but wreck us on the rocks of presumption or despair. But the light of divine life in the soul is accompanied with all the graces of the Spirit. It is the light of the glory of God, the light of Jesus' countenance, and the light of the Spirit's teaching, and therefore an infallible guide and guard; as the Apostle says, "You have an unction from the Holy One, and know all things." And this infallible pilot will guide the soul to whom it is given safe into the harbor of endless rest and peace.