There was the true Light which, coming into the world, enlightens every man.John 1:9(NASB)
We who were born in trespasses and sins, were groping about in deep darkness before we trusted in Christ for salvation and became children of light in the Lord Jesus. Down through the centuries, there have been many that claim to be 'illumined ones' but they are all deceived for they choose to believe the lie - for there is only One True Light Who gives light to all who comes into the world.
The Lord Jesus is that true and living light Who enlightens every person born in to the human race. But man has a dangerous enemy, a fallen angel called the devil and Satan, who desired to be as God and disguises himself as an angel of light, to deceive the nations.
As the second Member of the triune Godhead, the eternal Son has life in Himself and that life is the true light of men. Only those who have been born from above, by faith in Christ's redeeming work, are given the light of His life as an eternal possession and are brought into the radiance of His unconditional love.
Every man who has ever been born into this world has some illumination from God, for it is not God's will that any should perish. All have received the exterior light of creation, and all are given the inner light of conscience - and as a result of the light that man has received from God, all are responsible before Him, for all possess the truth of His existence and yet many refuse to acknowledge the true and living God.
God knows the heart and reads the secret thoughts and intents of men, and those who seek to know Him with all their heart will be found of Him and will be shown the true light in Whom alone is the salvation of the soul - and will be brought to a knowledge of the glorious gospel of Christ. But many choose to arrogantly deny His name, foolishly reject His existence, and stubbornly refuse His salvation. Such people will remain in the darkness that they have chosen and will remain in the darkness that they themselves have chosen - a choice made time but which will remain into eternity.
We however are God's adoptive children, because we have received the light of life in our hearts and trusted the Lord Jesus as Saviour. Therefore, we are to set our affection on things above and to walk in the light as He is in the light - for God Who commanded the light to shine out of darkness, has shone into our hearts to give us the light of the knowledge of the glory of God in the face of Jesus Christ.
Heavenly Father, I praise and thank You that You have placed Your Holy Spirit of light into our hearts to lead, direct, govern, and train us. Help me to walk in the light of Your love and truth, and may the beauty of Christ shine through me to others so that they too may come to a saving knowledge of our Saviour, Who is the true and only light, and in Whom is life eternal. This I ask in His name, AMEN.