What does the Bible say about fallen angels?

The scriptures make it clear that God did not forgive the fallen angels who rebelled against Him. In 2 Peter 2:4, it states, 'For if God did not spare the angels when they sinned, but cast them into hell and committed them to chains of gloomy darkness to be kept until the judgment.' This serves as a stern reminder of God's justice and the severity of His judgment for those who seek to usurp His authority. Unlike humanity, there is no redemption plan provided for angels who fall from grace, emphasizing the gravity of their rebellion.