It is here taken for granted that nothing but sin can be the cause of God’s inflicting punishment, and nothing can be sin which is not a breach of duty.

“Go ye into all the world, and preach the gospel to every creature. He that believeth and is baptized shall be saved; but he that believeth not shall be damned.” This awful passage appears to be a kind of ultimatum, or last resolve. It is as if our Lord had said, This is your message … go and proclaim it to all nations: whosoever receives it, and submits to my authority, assure him from me that eternal salvation awaits him; but whosoever rejects it, let him see to it … damnation shall be his portion! Believing and not believing, in this passage, serve to explain each other. It is saving faith to which salvation is promised, and to the want of this it is that damnation is threatened.

It has been alleged, that “as it is not inferrible from that declaration that the faith of believers is the procuring cause of their salvation, so it is not to be inferred from thence that the want of that special faith in unbelievers is the procuring cause of their damnation. That declaration contains in it the descriptive characters of those who are saved, and of those who are damned; but it assigns not special faith to be the procuring cause of the salvation of the former, nor the want of it to be the procuring cause of the damnation of the latter.”†

But if this mode of reasoning were admitted, we should find it very difficult, if not impossible, to prove any thing to be evil from the threatenings of God against it. A multitude of plain texts of Scripture, wherein sin, as any common reader would suppose, is threatened with punishment, might, in this manner, be made to teach nothing with regard to its being the procuring cause of it. For example, Psal. 37:18, 20, “The Lord knoweth the days of the upright; and their inheritance shall be for ever. But the wicked shall perish, and the enemies of the Lord shall be as the fat of lambs: they shall consume; into smoke shall they consume away.” But it might be said, as the uprightness of the upright is not the procuring cause of his enjoying an everlasting inheritance, so neither will this prove that the wickedness of the wicked, or the enmity of the Lord’s enemies, is the procuring cause of their being consumed. Again, Psal. 147:6, “The Lord lifteth up the meek; he casteth the wicked down to the ground.” But it might be alleged, that as the meekness of the former is not the procuring cause of his being lifted up, so it cannot be from hence inferred that the wickedness of the latter is the procuring cause of his being cast down. Again, Psal. 145:20, “The Lord preserveth all them that love him: but all the wicked will he destroy.” But it might be said, as the love of the one is not the procuring cause of his preservation, so it cannot be proved from hence that the wickedness of the other is the procuring cause of his destruction; and that these declarations contain only the “descriptive characters” of those who are saved, and of those who perish.

In this manner almost all the threatenings in the book of God might be made to say nothing as threatenings; for the mode in which they are delivered is the same as that in the passage in question. For example, “What shall be given unto thee? or what shall be done unto thee, thou false tongue? Sharp arrows of the mighty, with coals of juniper.”—“He that showeth no mercy shall have judgment without mercy.”—“Whoremongers and adulterers God will judge.”—“Be not deceived: neither fornicators, nor idolaters, nor adulterers, nor effeminate, nor abusers of themselves with mankind, nor thieves, nor covetous, nor drunkards, nor revilers, nor extortioners, shall inherit the kingdom of God.”—“Behold, the day cometh that shall burn like an oven, and all the proud, yea, and all that do wickedly, shall be stubble.”—“Bring hither those mine enemies, which would not that I should reign over them, and slay them before me.”—“The fearful, and unbelieving, and abominable, and murderers, and whoremongers, and sorcerers, and idolaters, and all liars, shall have their portion in the lake which burneth with fire and brimstone; which is the second death.” But none of these awful threatenings declare that the respective crimes which are mentioned are the procuring cause of the evils denounced. Though it is said concerning the “false tongue,” that “sharp arrows of the mighty, with coals of juniper,” shall be given him; yet it does not say that these shall be given him because of his falsehood; and so on of the rest. And thus they may be only “descriptive characters” of those who shall be damned; and all these things may, for aught these denunciations prove, be blameless. If this reasoning be just, it cannot be inferred, from the laws of England declaring that a murderer shall be put to death, that it is on account of his being a murderer. Neither could our first parents justly infer, from its being told them, “The day ye eat thereof ye shall surely die,” that it should be on that account.

The truth is, though eternal life be the gift of God, yet eternal death is the proper wages of sin; and though faith is not represented in the above passage as the procuring cause of salvation, yet unbelief is of damnation. It is common for the Scriptures to describe those that shall be saved by something which is pleasing to God, and by which they are made meet for glory; and those that shall be lost by something which is displeasing to God, and by which they are fitted for destruction.

John 3:18, “He that believeth on him is not condemned: but he that believeth not is condemned already, because he hath not believed in the name of the only begotten Son of God.” Two things are here observable. First, Believing is expressive of saving faith, seeing it exempts from condemnation. Secondly, The want of this faith is a sin on account of which the unbeliever stands condemned. It is true that unbelief is an evidence of our being under the condemnation of God’s righteous law for all our other sins; but this is not all: unbelief is itself a sin which greatly aggravates our guilt, and which, if persisted in, gives the finishing stroke to our destruction. That this idea is taught by the evangelist appears, partly from his dwelling upon the dignity of the character offended, the “only begotten Son of God;” and partly from his expressly adding, “this is the condemnation, that light is come into the world, and men loved darkness rather than light, because their deeds were evil.”

Luke 19:27, “But those mine enemies, which would not that I should reign over them, bring hither, and slay them before me.” If Christ, as wearing his mediatorial crown, has not a right to unreserved submission and hearty obedience, he has no right to be angry; and still less to punish men as his enemies for not being willing that he should reign over them. He has no right to reign over them, at least not over their hearts, if it be not their duty to obey him from their hearts. The whole controversy, indeed, might be reduced to an issue on this argument. Every sinner ought to be Christ’s friend, or his enemy, or to stand by as neutral. To say he ought to be his enemy is too gross to be defended. To plead for his being neutral is pleading for what our Lord declares to be impossible: “He that is not with me is against me.” There is, therefore, no room for any other position than that he ought to be his cordial friend; and this is the plain implication of the passage.

2 Thess. 2:10–12, “Whose coming is—with all deceivableness of unrighteousness in them that perish; because they received not the love of the truth, that they might be saved. And for this cause God shall send them strong delusion, that they should believe a lie: that they all might be damned who believed not the truth, but had pleasure in unrighteousness.” From hence we may remark two things: First, That faith is here called a receiving the love of the truth; and that it means saving faith is manifest, seeing it is added, “that they might be saved. Secondly, That their not receiving the love of the truth, or, which is the same thing, not believing with such a faith as that to which salvation is promised, was the “cause” of their being given up of God, and carried away with all deceivableness of unrighteousness. The loose and cold-hearted manner in which merely nominal Christians held the truth would occasion the introduction of the grand papal apostacy, by which great numbers of them would be swept away. And this, assuredly, ought to afford a lesson to nominal Christians of the present day, who, owing to the same cause, are fast approaching to infidelity. But unless we suppose that these professors of religion ought to have “received the love of the truth,” there is no accounting for the awful judgments of God upon them for the contrary.

Fuller, A. G. (1988). “Unbelief is Ascribed to Men’s Depravity and is Its Self a Heinous Sin,” Proportion IV. Part II, The Gospel Worthy of All Acceptation. The Complete Works of Andrew Fuller: Controversial Publications (J. Belcher, Ed.; Vol. 2, pp. 358–360). Sprinkle Publications.