How do we know the doctrine of light and darkness is true?

The validity of the doctrine of light and darkness is rooted in the person and work of Jesus Christ as revealed in Scripture. In John 3:20-21, we find that those who do evil hate the light because it exposes their deeds, while those who seek the truth embrace the light. This illustrates the stark reality of human nature: people often resist the truth of God's Word, preferring darkness to avoid the exposure of their sin. Furthermore, historical testimony of God's revelation through the ages, culminating in Christ, shows that light in the form of the gospel has continually been about the proclamation of truth amidst a backdrop of darkness. Ultimately, our confidence lies in the revelation of God through scripture, asserting the continual need for His light in our lives.