Read Matthew 13:24-30, known as the parable of the weeds. While there may be some of the parable that is easily understood, the closest followers of Jesus didn't understand it all. Later in the chapter they asked Jesus to explain it to them.
37 He answered, “The one who sowed the good seed is the Son of Man. 38 The field is the world, and the good seed stands for the sons of the kingdom. The weeds are the sons of the evil one, 39 and the enemy who sows them is the devil. The harvest is the end of the age, and the harvesters are angels.
40 “As the weeds are pulled up and burned in the fire, so it will be at the end of the age. 41 The Son of Man will send out his angels, and they will weed out of his kingdom everything that causes sin and all who do evil. 42 They will throw them into the fiery furnace, where there will be weeping and gnashing of teeth. 43 Then the righteous will shine like the sun in the kingdom of their Father. He who has ears, let him hear. Matthew 13:36-43
Jesus went into great detail in his explanation, naming everything and everyone involved. That gives his disciples a little more information in learning the meaning of the parable. Then Jesus tells how all of it fits into his description of events at the end of the age.
Look again at those events. The weeds are pulled up and burned in the fire. The Son of Man sends his angels, whose duty consists of weeding out of the kingdom everything that causes sin and all who do evil. They end up in the fiery furnace, that place of weeping and gnashing of teeth.
That description makes me shiver. It is a fearful description Jesus gives. It could even be the motivation for some to become "sons of the kingdom" and known to be "the good seed."
Notice again verse 43 from above. It is the description Jesus gives for the righteous. We who have escaped darkness and have lived lives of "walking in the light" are described in words which could be considered the greatest promise in the Bible. " Then the righteous will shine like the sun in the kingdom of their Father."
As children of God, we recognize the responsibility to the be light of the world. Our lives as Christians can be a blessing to those around us as they see Jesus living in us. Even greater, when Jesus comes and weeds out everything that causes evil and all who do evil, he promises we are going to still be shining; shining like the sun in the kingdom of the Father. Earlier in Matthew he had said, "Let your light so shine before men, that they may see your good works, and give glory to your Father in heaven."