giving vengeance to those who don't know God, and to those who don't obey the Gospel of our Lord Jesus,
God is represented as appearing in flaming fire when He manifested Himself to Moses in the burning bush (Exodus 3:2; Acts 7-30). Paul writes in 1 Corinthians 3:13, "Every man’s work shall be made manifest: for the day shall declare it, because it shall be revealed by fire; and the fire shall try every man’s work of what sort it is." What has earlier been said of God is also said of Christ. The fact is when God and Christ return, They will come with "flaming fire"; and it will indeed be a terrible day for those unprepared to meet Him.