The words that speak most strongly about a fiery future, such as the lake of fire of Revelation 20:14, are symbolic of the destruction that will occur at the future time of Judgment. However, 2 Peter 3:10-13, speaking of the time when Jesus Christ returns to the earth, says,
But the day of the Lord will come like a thief, and then the heavens will pass away with a roar, and the heavenly bodies will be burned up and dissolved, and the earth and the works that are done on it will be exposed. Since all these things are thus to be dissolved, what sort of people ought you to be in lives of holiness and godliness, waiting for and hastening the coming of the day of God, because of which the heavens will be set on fire and dissolved, and the heavenly bodies will melt as they burn! But according to his promise we are waiting for new heavens and a new earth in which righteousness dwells.
Even though this is speaking figuratively of the end of the world’s political systems, the strong use of the figure of fire suggests the possibility that there will be a time of literal fiery trouble.