Charles H. Spurgeon on Psalms 97:3

A fire goeth before him. That fire which Christ came to send upon the earth, the kindling blaze of the Holy Ghost, which came down in tongues of fire at Pentecost, to burn freely throughout the world, for the destruction of obstinate unbelievers, and the purifying of those who gladly received the Word. And of this the prophet spake, saying, "I will send a fire on Magog, and among them that dwell carelessly its the isles: and they shall know that I am the LORD." (Eze 39:6.) This divine flame goes still before the face of the Lord in his coming to every faithful soul, as it kindles with longing for him, and burns up all its sins therewith, as he heaps his coals of fire upon its head, to soften and purify it. "It must needs be", teaches a great saint, (S. Bernard.) "that the fervour of holy desire must go before his face to every soul to which he means to come, a flame which will burn up all the mildew of sin, and make ready a place for the Lord. And then the soul knows that the Lord is at hand, when it feels itself kindled with that fire, and it saith with the prophet, `My heart was hot within me; then spake I with my tongue.'"(Ps 39:3). —Augustine, and others, quoted by Neale and Littledale.