In flaming fire taking vengeance on them {6} that know not God, and that obey not the gospel of our Lord Jesus Christ:

(6) There is no knowledge of God to salvation, without the Gospel of Christ.

People's New Testament

1:8 In flaming fire. The flaming fire denotes brightness, glory, purity, and also destruction to adversaries. Dazzling brightness is always associated with his coming. God was revealed at Sinai in flaming fire (Ex 3:2; 19:18).

Them that know not God. Know him not because they refuse to know him. See Ro 1:28.

And obey not the gospel. This class refuse to accept and obey the gospel. Their day of grace will end with the day of the Lord.

Wesley's Notes

1:8 Taking vengeance - Does God barely permit this, or (as the Lord once rained brimstone and fire from the Lord out of heaven, Gen 19:24) does a fiery stream go forth from him for ever? Who know not God - (The root of all wickedness and misery) who remain in heathen ignorance. And who obey not - This refers chiefly to the Jews, who had heard the gospel.

King James Translators' Notes

taking: or, yielding

Jamieson-Fausset-Brown Bible Commentary

8. In flaming fire-Greek, "In flame of fire"; or, as other oldest manuscripts read, "in fire of flame." This flame of fire accompanied His manifestation in the bush (Ex 3:2); also His giving of the law at Sinai (Ex 19:18). Also it shall accompany His revelation at His advent (Da 7:9, 10), symbolizing His own bright glory and His consuming vengeance against His foes (Heb 10:27; 12:29; 2Pe 3:7, 10).

taking-literally, "giving" them, as their portion, "vengeance."

know not God-the Gentiles primarily (Ps 79:6; Ga 4:8; 1Th 4:5); not of course those involuntarily not knowing God, but those wilfully not knowing Him, as Pharaoh, who might have known God if he would, but who boasted "I know not the Lord" (Ex 5:2); and as the heathen persecutors who might have known God by the preaching of those whom they persecuted. Secondarily, all who "profess to know God but in works deny Him" (Tit 1:16).

obey not the gospel-primarily the unbelieving Jews (Ro 10:3, 16); secondarily, all who obey not the truth (Ro 2:8).

Christ-omitted by some of the oldest manuscripts, and retained by others.

Matthew Henry's Concise Commentary

1:5-10 Religion, if worth anything, is worth every thing; and those have no religion, or none worth having, or know not how to value it, cannot find their hearts to suffer for it. We cannot by all our sufferings, any more than by our services, merit heaven; but by our patience under sufferings, we are prepared for the promised joy. Nothing more strongly marks a man for eternal ruin, than a spirit of persecution and enmity to the name and people of God. God will trouble those that trouble his people. And there is a rest for the people of God; a rest from sin and sorrow. The certainty of future recompence is proved by the righteousness of God. The thoughts of this should be terrible to wicked men, and support the righteous. Faith, looking to the great day, is enabled partly to understand the book of providence, which appears confused to unbelievers. The Lord Jesus will in that day appear from heaven. He will come in the glory and power of the upper world. His light will be piercing, and his power consuming, to all who in that day shall be found as chaff. This appearance will be terrible to those that know not God, especially to those who rebel against revelation, and obey not the gospel of our Lord Jesus Christ. This is the great crime of multitudes, the gospel is revealed, and they will not believe it; or if they pretend to believe, they will not obey it. Believing the truths of the gospel, is in order to our obeying the precepts of the gospel. Though sinners may be long spared, they will be punished at last. They did sin's work, and must receive sin's wages. Here God punishes sinners by creatures as instruments; but then, it will be destruction from the Almighty; and who knows the power of his anger? It will be a joyful day to some, to the saints, to those who believe and obey the gospel. In that bright and blessed day, Christ Jesus will be glorified and admired by his saints. And Christ will be glorified and admired in them. His grace and power will be shown, when it shall appear what he has purchased for, and wrought in, and bestowed upon those who believe in him. Lord, if the glory put upon thy saints shall be thus admired, how much more shalt thou be admired, as the Bestower of that glory! The glory of thy justice in the damnation of the wicked will be admired, but not as the glory of thy mercy in the salvation of believers. How will this strike the adoring angels with holy admiration, and transport thy admiring saints with eternal rapture! The meanest believer shall enjoy more than the most enlarged heart can imagine while we are here; Christ will be admired in all those that believe, the meanest believer not excepted.