Weeping and gnashing of teeth definitely means one thing; if annihilation occurs, it won’t be immediate.
Yes the letter of the law kills. In dying the corrupted flesh returns to the dust and the corrupted spirit return to the father who temporarily gave it. . subject to the letter of the law...that kills .The letter of the law will be cast into the lake of fire never to rise to condemn a creation ever again.
2 Corinthians 6:9 King James Version (KJV) As unknown, and yet well known; as dying, and, behold, we live; as chastened, and not killed;