Prolegomena: A Foundation of Theological Study

The core soteriological promise of the New Testament is straightforward: belief in Christ guarantees the possession of everlasting life. For example, Jesus declares in John 6:47, “Most assuredly, I say to you, he who believes in Me has everlasting life.” In this proposition, simple faith in Christ functions as a sufficient condition for possessing eternal life. The fallacy of Denying the Antecedent occurs when an interpreter takes a conditional premise regarding discipleship or sanctification—such as “If a believer endures, he will reign with Christ” (2 Tim 2:12a)—and incorrectly infers: “Therefore, if a person does not endure, he is not eternally saved.” Paul explicitly refutes this logical fallacy in the very next verse: “If we are faithless, He remains faithful; He cannot deny Himself” (2 Tim 2:13). While unfaithfulness forfeits the reward of reigning, it does not and cannot negate the possession of eternal life, which was received as an unearned, irrevocable gift (Eph 2:8–9). Confusing a sufficient condition for entrance into heaven with necessary conditions for temporal discipleship collapses justification into works, undermining the believer’s absolute assurance.

In soteriological discussions, logical precision is as critical as grammatical exactness. A frequent logical misstep committed by proponents of Lordship Salvation is the formal fallacy of affirming the consequent. By asserting that “If a person is saved, they will perform good works,” and observing good works, interpreters fallaciously infer that those works prove regeneration. Conversely, observing an absence of works is wrongly assumed to prove an absence of faith. This blog post examines how conditional logic functions in New Testament Greek and demonstrates why biblical assurance rests solely upon the explicit promise of Jesus Christ to the believer, rather than on logical fallacies applied to post-conversion behavior.