Again, the kingdom of heaven is like a net that was thrown into the sea and gathered fish of every kind.  When it was full, men drew it ashore and sat down and sorted the good into containers but threw away the bad.  So it will be at the close of the age.  The angels will come out and separate the evil from the righteous and throw them into the fiery furnace.  In that place there will be weeping and gnashing of teeth.

Matthew 13:47-50

Jesus is likely talking about a dragnet, a large fishing net equipped with a weighted bottom edge and wooden floats that would allow the net to be spread across the water.  Dragnets are designed to drop to the bottom and drag, catching fish and other sea creatures along the way.  After fishermen in boats let the the nets down, fishermen on the shore would drag the nets to the shore.  If it was a large catch, the guys in the boat would help.  Once upon land, they would separate the fish in the net.  Fish good for eating would be put into containers.  Everything else would be thrown away.

A parable literally is defined as a comparison.  He’s comparing the kingdom of heaven — the church (Col. 1:13; 1 Thess. 2:12; Heb. 12:28) — to this net.  Why?

Within the church, there are Christians who are faithful and Christians who are unfaithful.  Church discipline weeds out unfaithful Christians whose sins are known (1 Cor. 5; 2 Thess. 3:6, 14-15; Rom. 16:17-18; Matt. 18:15-17).

Yet not everyone’s sins are always known in this life (1 Tim. 5:24).  Thus, within God’s kingdom there are faithful followers…and unfaithful followers (2 Tim. 2:20-21).

At the close of the age, something very similar to fishermen separating good fish from the bad will happen on the day of judgment.  “The Son of Man will send his angels, and they will gather out of his kingdom all causes of sin and all lawbreakers, and throw them into the fiery furnace.  In that place there will be weeping and gnashing of teeth.”  (Matt. 13:41-42)

On that great and terrible day, both the righteous and the wicked will be resurrected, and the wicked will be condemned (John 5:24-29).  They will be separated from God and cast into hell (Matt. 18:8-9; 25:41), where they will suffer torment in fire and darkness for all eternity (Rev. 21:8; Matt. 25:30, 46; 2 Thess. 1:7-9).

The righteous will also be judged (2 Cor. 5:10; Matt. 25:31-34), after which they will be ushered into heaven where their citizenship and inheritance is waiting for them (Phil. 3:20-21; 1 Pet. 1:3-5).  In heaven they will rest in God’s glory forever (John 17:24; Rom. 2:7, 10; Matt. 25:46; Rev. 14:13).

If you want to go to heaven by the grace of God, hear God’s Word in order to produce the faith in Jesus you need to both possess and confess (Rom. 10:17; John 3:16; Matt. 10:32-33).  Repent of your sins and wash them away through baptism into Christ (Acts 17:30; 2:38; 22:16; Gal. 3:26-27; 1 Pet. 3:21; Mk. 16:16).

At that point you will become a Christian and salvation and forgiveness will be granted to you.  Afterwards, choose to live faithfully, penitently, and obediently in the sight of God for the rest of your days, and you will never lose your salvation (1 John 1:7-9; Heb. 5:9; Matt. 28:19-20).