'Second Death' in the Bible

He who has an ear, let him hear and heed what the Spirit says to the churches. He who overcomes [the world through believing that Jesus is the Son of God] will not be hurt by the second death (the lake of fire).’

Blessed (happy, prosperous, to be admired) and holy is the person who takes part in the first resurrection; over these the second death [which is eternal separation from God, the lake of fire] has no power or authority, but they will be priests of God and of Christ and they will reign with Him a thousand years.

Then death and Hades [the realm of the dead] were thrown into the lake of fire. This is the second death, the lake of fire [the eternal separation from God].

But as for the cowards and unbelieving and abominable [who are devoid of character and personal integrity and practice or tolerate immorality], and murderers, and sorcerers [with intoxicating drugs], and idolaters and occultists [who practice and teach false religions], and all the liars [who knowingly deceive and twist truth], their part will be in the lake that blazes with fire and brimstone, which is the second death.”