In Genesis 4:23, this signifies to extinguish faith. (Arcana Coelestia 427)

'The slain of Jehovah' signify people who turn truths into falsities, which causes them to perish.

'The slain,' in Lamentations 2:12 signify people who do not know what the truths of faith mean.

'The slain' when referring to the Lord in Revelation 5 means the separation of everything from the divine. In denial of His divinity, He is spiritually slain to people and this denial causes a state of separation from Him.

(Reference: Lamentations 2; The Apocalypse Explained 828)

427. Verse 23 And Lamech told his wives Adah and Zillah, Hear my voice, O wives of Lamech, and with your ears perceive my speech that I have killed a man (vir) to my wounding, and a little one to my bruising. 'Lamech', as previously, means vastation. 'He told his wives Adah and Zillah to perceive with their ears his speech' means confession such as is not otherwise made except where a Church exists, which, as has been stated, is meant by his wives.' He killed a man to his own wounding means that he annihilated faith, a man' meaning faith, as previously. 'A little one to his bruising' means that he annihilated charity. 'Wound' and 'bruise' mean a condition that was no longer sound, 'wound' meaning that faith had been desolated, and 'bruise' that charity had been laid waste.