People who Jesus says will weep and gnash their teeth

The children of the kingdom

But the children of the kingdom shall be cast out into outer darkness: there shall be weeping and gnashing of teeth. Matthew 8:12

Those who offend and do iniquity

The Son of man shall send forth his angels, and they shall gather out of his kingdom all things that offend, and them which do iniquity; And shall cast them into a furnace of fire: there shall be wailing and gnashing of teeth. Matthew 13:42

Wicked people

So shall it be at the end of the world: the angels shall come forth, and sever the wicked from among the just,

And shall cast them into the furnace of fire: there shall be wailing and gnashing of teeth. Matthew 13:49-50

Those who aren't wearing a wedding garment

When the king came in to see the guests, he saw there a man which had not on a wedding garment:

And he saith unto him, Friend, how camest thou in hither not having a wedding garment? And he was speechless.

Then said the king to the servants, Bind him hand and foot, and take him away, and cast him into outer darkness, there shall be weeping and gnashing of teeth. Matthew 22:11-13

Evil servants

The lord of that servant shall come in a day when he looketh not for him, and in an hour that he is not aware of,

And shall cut him asunder, and appoint him his portion with the hypocrites: there shall be weeping and gnashing of teeth. Matthew 24:50-51

Unprofitable servants

For unto every one that hath shall be given, and he shall have abundance: but from him that hath not shall be taken away even that which he hath.

And cast ye the unprofitable servant into outer darkness: there shall be weeping and gnashing of teeth. Matthew 25:29-30

People that Jesus doesn't know

But he shall say, I tell you, I know you not whence ye are; depart from me, all ye workers of iniquity.

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. Luke 13:27-28