Adam Clarke on Psalms 97:3

A fire goeth before him - Literally, this and the following verse may refer to the electric fluid, or to manifestations of the Divine displeasure, in which, by means of ethereal fire, God consumed his enemies. But fire is generally represented as an accompaniment of the appearances of the Supreme Being. He appeared on Mount Sinai in the midst of fire, thunder, and lightninys, Exo 19:16-18. Daniel, Dan 7:9, Dan 7:10, represents the Sovereign Judge as being on a throne which was a fiery flame, and the wheels of his chariot like burning fire; and a fiery streamer issuing from it, and coming forth from before him. St. Paul tells us (2Thes 1:8) that the Lord Jesus shall be revealed from heaven with his mighty angels, in faming fire; and St. Peter, (2Pet 3:7, 2Pet 3:10, 2Pet 3:11), that when the Lord shall come to judgment the heavens and the earth shall be destroyed by fire. the heavens shall pass away with a great noise, the elements melt with fervent heat, and the earth and its works be burnt up. Here then, will appear: - "Our God in grandeur, and our world on fire."

Burneth up his enemies round about - The fire is his pioneer which destroys all the hinderances in his way, and makes him a plain passage.