Matthew 13:47 "Again, the kingdom of heaven is like a net that was thrown into the sea and gathered fish of every kind. 48 When it was full, men drew it ashore and sat down and sorted the good into containers but threw away the bad. 49 So it will be at the close of the age. The angels will come out and separate the evil from the righteous 50 and throw them into the fiery furnace. In that place there will be weeping and gnashing of teeth.
Under God's rule the righteous and the unrighteous exist together. The righteous seek to live in obedience to the word of God and the unrighteous live according to their sin nature. Romans 6:16 describes the unrighteous and the righteous. Romans 6:16 "Do you not know that if you present yourselves to anyone as obedient slaves, you are slaves of the one whom you obey, either of sin, which leads to death, or of obedience which leads to righteousness?" Romans 8:5 describes the two different worldviews of the unrighteous and the righteous, "For those who live according to the sin nature set their minds on the things of the sin nature, but those who live according to the Spirit set their minds on the things of the Spirit." The unrighteous think and act according to the sin nature which leads to destructive lifestyles, which we see the consequences of every day. The righteous think and live according to God's word and live lives of restoration. Both live in this world together.
Just as a fisherman keeps the good fish and throws away the bad, so the Creator God, the Lord Jesus Christ will judge between the righteous and the unrighteous at the end of this present evil age when Jesus returns in power to rule and judge the world. Revelation 20:11-15 describes this judgment. Each person will have the "books of his/her life" open before the Judge and be judged according to what he/she did in life. James 2:10 tells us that if we have broken the law of God once, we have broken the whole law. Romans 3:23 tells us that all of us have sinned and are unrighteous. All are guilty and deserve the penalty for sin, the second death, the Lake of Fire, eternal torment (Romans 6:23; Revelation 20:14-15; 21:8; Matthew 25:46). However the Judge looks into another book, the Book of Life. If a person's name is written in the Book of Life, he/she is pardoned of sin and enters into eternal life, the new heavens and earth.
How does a person get his/her name written in the Book of Life? Jesus tells us how in Mark 1:15, ..."Repent and believe the gospel." Repent means to acknowledge and turn away from sin and turn to Jesus. Believing in the gospel means to believe Jesus died on the cross for our sin, was buried and rose again on the third day and that He is Lord and to be obeyed (1 Corinthians 15:3-4; Romans 10:9). Real faith has a desire to obey the Lord (Romans 1:5; James 2:14-26; 1 Peter 1:2,22). Those who believe the gospel are made righteous and receive the power to live righteously (Romans 5:1; 6:1-4; Ephesians 1:13-14; 3:20). What is your future? Can it be predicted by how you live think and live today?