Good quote from Brian Blount about judgment and the lake of fire and sulphur in Revelation 20:
“This portrait of God imposing eternal suffering seems as un-Christlike a punishment as imaginable. Yet John is dealing with the twin concepts of justice and mercy/grace. For him, one cannot exist without the other. For the evil that has been perpetrated, there needs to be justice, and he conceives of it in its most undiluted form as eternal suffering in the lake of fire and sulfur (brimstone). It is important to remember, however, that this is a figurative and not a literal ‘lake.’ What John is describing is not real, physical torture but the kind of continuous, perpetual spiritual torment that he imagines must occur when a being is separated forever from the presence of God. … He was trying to think of an image that would have ‘teeth’ for them, an image that would shock persons who were accommodating to the draconian lordship demands of Rome into resisting them and testifying in word and deed to the lordship of God and the Lamb instead. He wanted them to fear being forever separated from the presence of God. His most forceful metaphorical attempt at conveying what that separation would feel like is the lake of fire and sulfur (brimstone). A twenty-first-century effort should focus on the language of separation from God’s presence and look for a contemporary metaphor appropriate to that separation, one that does not include the image of physical torture, whether eternal or otherwise.”
Brian K. Blount, Revelation: A Commentary (NTL; Louisville, KY: Westminster John Knox, 2009), 371-72.