Somewhere in 1 Cor. that says our works will be tested through fiery trials to see what sort it is; if it’s burned, then you’ll still be saved, but no reward.
Also, all mentions of “weeping and gnashing of teeth” in Matthew were describing this, being shut out of the party and stranded in the streets at night.
The context of that passage in 1 Cor. Is teachers. But I don't recall anything there about rewards. Regarding weeping and gnashing of teeth, I believe that's a reference to an Old Testent passage that speaks of the wicked gnashing their teeth at the righteous.
Psalm 112
Praise ye the Lord.
Blessed is the man that feareth the Lord,
That delighteth greatly in his commandments.
His seed shall be mighty upon earth:
The generation of the upright shall be blessed.
Wealth and riches shall be in his house:
And his righteousness endureth for ever.
Unto the upright there ariseth light in the darkness:
He is gracious, and full of compassion, and righteous.
A good man sheweth favour, and lendeth:
He will guide his affairs with discretion.
Surely he shall not be moved for ever:
The righteous shall be in everlasting remembrance.
He shall not be afraid of evil tidings:
His heart is fixed, trusting in the Lord.
His heart is established, he shall not be afraid,
Until he see his desire upon his enemies.
He hath dispersed, he hath given to the poor;
His righteousness endureth for ever;
His horn shall be exalted with honour.
The wicked shall see it, and be grieved;
He shall gnash with his teeth, and melt away:
The desire of the wicked shall perish.