Luke 13:28

There shall be weeping and gnashing of teeth, when ye shall see Abraham, and Isaac, and Jacob, and all the prophets, in the kingdom of God, and you yourselves thrust out.

The verse pictures the final grief of those thrust out of God's kingdom when they see Abraham and Isaac and Jacob and all the prophets inside it while they themselves are excluded, and their response is weeping and gnashing of teeth in grief and anguish. It takes up a hope the Jews loved to dwell on, that the blessings of eternal life would be like a sacred feast where they would sit down with Abraham and Isaac and Jacob while the Gentiles stood outside looking on with longing eyes. Christ turned that cherished expectation into a lesson of warning and instruction, illustrated by the parable of a great supper, that those who expected to be inside could be left outside for rejecting God's invitation. The despised outsiders would instead receive the invitation of mercy and come from the east and the west and the north and the south to rest in the kingdom, for the last shall be first and the first last.

The warning belongs to Christ's teaching about personal salvation and the narrow entrance, where the time to enter ends when the Master rises and shuts the door. Those who then plead for the door to be opened will be disowned and driven away and rejected as workers of iniquity. Mere familiarity with Christ, outward acquaintance with Him, hearing His teaching, religious privilege, or having heard the truth does not secure entrance. Entry is for those who seek with earnest obedience, not for those who choose the way of iniquity.

It was spoken to the teachers in Israel, the scribes and Pharisees, whose spiritual blindness came from refusing light and the working of the Holy Spirit despite abundance of evidence. They made void the commandments of God, missed the true meaning of the Sabbath and turned it into bondage, and set up false outward ceremonial standards in place of spiritual requirements. The words amazed them because with the great light given them they regarded themselves as the first and only pious people on earth. On hearing they would be last and shut out, they determined to get rid of Christ by intimidation.

The same exclusion threatens those who profess faith yet persist in dishonest practices and refuse to be purified. Religious privilege does not save when a person chooses iniquity, and such will grieve in anguish to see the patriarchs and prophets in the kingdom while they are shut out. Specifically those who remain covetous and refuse to make restitution will see God's saints glorified in the heavenly city yet be thrust out themselves. They will have no share in the life purchased at infinite cost.