For God who said, “Let light shine out of darkness,” has shone in our hearts to give the light of the knowledge of God’s glory in the face of Jesus Christ.2 Corinthians 4:6 HCSB

Then God said, “Let there be light,” and there was light. God saw that the light was good, and God separated the light from the darkness. God called the light “day,” and He called the darkness “night.” Evening came and then morning: the first day.

Genesis 1:3‭-‬5 HCSB
https://bible.com/bible/72/gen.1.3-5.HCSB

Light is very important to God. In the beginning, He created light on the first day. He then started His important work in creation. God does not work in the dark hiding what he is doing. And He does not want His kids, children, and followers walking in the dark. Instead, He shines His light into our lives to illuminate the dark places where sin continues to live in our lives.

For godly grief produces a repentance not to be regretted and leading to salvation, but worldly grief produces death.
2 Corinthians 7:10 HCSB
https://bible.com/bible/72/2co.7.10.HCSB

Part of God's light is His Godly grief to produce repentance in us. But the light of the world produces regret in our lives, but God uses His light to shine into our hearts to let us know that we need to repent and turn away from our sins.

The Lord said to me, “Son of man, look toward the north.” I looked to the north, and there was this offensive statue north of the altar gate, at the entrance. He said to me, “Son of man, do you see what they are doing here, more detestable things that the house of Israel is committing so that I must depart from My sanctuary? You will see even more detestable things.”
Then He brought me to the entrance of the court, and when I looked there was a hole in the wall. He said to me, “Son of man, dig through the wall.” So I dug through the wall, and there was a doorway. He said to me, “Go in and see the terrible and detestable things they are committing here.” I went in and looked, and there engraved all around the wall was every form of detestable thing, crawling creatures and beasts, as well as all the idols of the house of Israel.
Ezekiel 8:5‭-‬10 HCSB
https://bible.com/bible/72/ezk.8.5-10.HCSB

Ezekiel got to see what was happening behind the walls of the temple because God was shedding light to expose these wicked things.

When the king of Aram was waging war against Israel, he conferred with his servants, “My camp will be at such and such a place.” But the man of God sent word to the king of Israel: “Be careful passing by this place, for the Arameans are going down there.” Consequently, the king of Israel sent word to the place the man of God had told him about. The man of God repeatedly warned the king, so the king would be on his guard. The king of Aram was enraged because of this matter, and he called his servants and demanded of them, “Tell me, which one of us is for the king of Israel? ” One of his servants said, “No one, my Lord the king. Elisha, the prophet in Israel, tells the king of Israel even the words you speak in your bedroom.”
2 Kings 6:8‭-‬12 HCSB
https://bible.com/bible/72/2ki.6.8-12.HCSB

Elisha was given light to see and hear what the king of Aram was planning so that the king of Isreal would be prepared for him.

“Neither this man nor his parents sinned,” Jesus answered. “This came about so that God’s works might be displayed in him. We must do the works of Him who sent Me while it is day. Night is coming when no one can work. As long as I am in the world, I am the light of the world.”
John 9:3‭-‬5 HCSB
https://bible.com/bible/72/jhn.9.3-5.HCSB

While Jesus walked the earth He was light to those who would listen.

“You are the light of the world. A city situated on a hill cannot be hidden.  No one lights a lamp and puts it under a basket,   but rather on a lampstand, and it gives light for all who are in the house.  In the same way, let your light shine before men, so that they may see your good works and give glory to your Father in heaven.
Matthew 5:14‭-‬16 HCSB
https://bible.com/bible/72/mat.5.14-16.HCSB

Now we are His light in this world. We are set apart to be a beacon to those who cross our path.

Now the works of the flesh are obvious:  sexual immorality, moral impurity, promiscuity,  idolatry, sorcery, hatreds, strife, jealousy, outbursts of anger, selfish ambitions, dissensions, factions,  envy,  drunkenness, carousing, and anything similar. I tell you about these things in advance — as I told you before — that those who practice such things will not inherit the kingdom of God.
But the fruit of the Spirit is love, joy, peace, patience, kindness, goodness, faith,  gentleness, self-control. Against such things there is no law.
Galatians 5:19‭-‬23 HCSB
https://bible.com/bible/72/gal.5.19-23.HCSB