How do we know that Christians are called to be light in the world?

In John 8:12, Jesus states, 'I am the light of the world; he that followeth me shall not walk in darkness but shall have the light of life.' This indicates that those who follow Christ are filled with His light, which enables them to navigate the darkness of sin and ignorance. The believer’s light is not self-generated; rather, it reflects the light of Christ and His teachings. As Paul writes in 2 Corinthians 4:6, God shines His light in our hearts, granting us the knowledge of His glory. Therefore, Christians are to reflect this light by living out their faith authentically and boldly in a darkened world.