Heb 12:29

“And whatever other such statements they advance respecting this (Aeon), these they allege to hold good of the animalish (one), whom they assert to be creator of the world. Now he is of the appearance of fire. Moses also, he says, expresses himself thus: "The Lord thy God is a burning and consuming fire." For he, likewise, wishes (to think) that it has been so written. There is, however, he says, a twofold power of the fire; for fire is all-consuming, (and) cannot be quenched.”

“In sacred language God is called a fire, as when Scripture says, "Our God is a consuming fire." Concerning the substance of the angels, it also speaks as follows: "Who makes his angels spirits and his ministers a burning fire." And in another place, "The angel of the Lord appeared in a flame of fire in the bush." In addition, we have received a command to be "fervent in spirit" by which expression undoubtedly the word of God is shown to be hot and fiery. The prophet Jeremiah also hears from him who gave him oracles, "Behold, I am making my words in your mouth a fire." As God, then, is a "fire" and the angels are "flames of fire" and all the saints are "fervent in spirit," so, on the contrary, those who have fallen away from the love of God are undoubtedly said to have cooled in their affection for God and to have become cold.”

“Many have produced lengthy discussions of God and God's essence. Some have even said that God has a bodily nature that is composed of fine particles and is like ether. Others have said that God is incorporeal and is of a different essence that transcends bodies in dignity and power. For this reason it is worthwhile for us to see if we have resources from the divine Scriptures to say something about God's essence. In John 4:24 it is stated as if God's essence were spirit, for it says, "God is spirit." But in the law, it is instead as if God's essence were fire, for it is written, "Our God is a consuming fire." In John, however, it is stated as if God were light, for John says, "God is light, and in him is no darkness at all." If, then, we should listen to these words literally, making no inquiry beyond the letter, we would have to say that God is a body.… But because we do not see the consequences if we attribute a body to God when we say, even on the basis of Scripture, that God is some such body as spirit, or consuming fire, or light, unless we accept the conclusions that necessarily follow these assertions, we will disgrace ourselves as foolish and contradicting the obvious. For every fire is subject to extinction because it needs fuel; and every spirit, even if we take the spirit to be simple, because it is a body, admits of change to what is coarser in its own nature. In these matters, then, we must either accept so many absurd and blasphemous things about God in preserving the literal meanings, or, as we also do in many other cases, examine and inquire what can be meant when it is said that God is spirit or fire or light. First we must say that just as when we find it written that God has eyes, eyelids, ears, hands, arms, feet, and even wings, we change what is written into an allegory, despising those who bestow on God a form resembling humans; and we do this with good reason. So also must we act consistently with our practice in the case of the names mentioned above.”

“"For our God is a consuming fire." These things, he means, are terrible; and so terrible that they could not even bear to hear them, that not even "a beast" dared to go up. But things that come hereafter are not such. For what is Sinai to Heaven? And what the "fire which might be touched" to God who cannot be touched? For "God is a consuming fire."”

“Having shown, on the one hand, that the Old Testament events inspire fear, and on the other, that in the New Testament there is nothing of the sort, he, lest they treat the gentleness with contempt, says: let us offer gratitude to God with reverence and fear. For the soul, giving in to despair during calamities, loses its shame. Or: our service must be performed with reverence and fear. For our God is a fire, and therefore we must have fear, lest He destroy us as negligent and indifferent. For it says: let the sons of Israel be reverent. This also provides them consolation, namely that we have such a God Who is able to consume our enemies.”

“725. – That we should serve God in that manner he proves by the authority of Deuteronomy (4:24): For our God is a consuming fire. When God is said to be a fire, it does not mean that He is something corporeal, but it is because intelligible things are designated by sense-perceptible things, among which fire has greater nobility and clarity; and greater activity; and a higher natural place; and is more cleansing and more consuming. Therefore, God is especially called fire on account of His clarity, because He inhabits light inaccessible (1 Tim. 6:16), and because He is supremely active: 'You have worked all our works in us' (Is. 26:12), and He is in a loftier place: 'The Lord is high above all nations; and his glory above the heavens' (Ps. 112:4). Furthermore, he cleanses and as it were, consumes sins; hence, he says that he is a consuming fire: 'He is like a refining fire' (Mal. 3:2); and he continues: 'And he shall purify the sons of Levi'; 'making purgation of sins' (Heb. 1:3). He also consumes sinners by punishing: 'But a certain dread in expectation of judgement and the rage of a fire that shall consume the adversaries' (Heb. 10:27). Therefore, because such things are promised to us: 'And the light of Israel shall be as a fire, and the Holy One thereof as a flame' (Is. 10:17); 'A fire shall go before them and shall burn up enemies round about' (Ps. 96:3), we should strive to serve and please God.”

“Syncletica said, 'All must endure great travail and conflict when they are first converted to the Lord but later they have unspeakable joy. They are like people trying to light a fire, the smoke gets in their eyes, their eyes begin to water, but they succeed in what they want. It is written, "Our God is a consuming fire" (Heb. 12:29), and so we must kindle divine fire with tears and trouble.'”

“Lot went to Joseph and said, 'Abba, as far as I can, I keep a moderate rule, with a little fasting, and prayer, and meditation, and quiet: and as far as I can I try to cleanse my heart of evil thoughts. What else should I do?' Then the hermit stood up and spread out his hands to heaven, and his fingers shone like ten flames of fire, and he said, 'If you will, you can become all flame.'”