Original Word: ἀπιστέω
Part of Speech: Verb
Transliteration: apisteó
Pronunciation: ah-pees-TEH-oh
Phonetic Spelling: (ap-is-teh'-o)
KJV: believe not
NASB: believe, disbelieve, disbelieved, faithless, refused to believe, would not believe
Word Origin: [from G571 (ἄπιστος - unbelieving)]

1. to be unbelieving
2. (transitively) disbelieve
3. (by implication) disobey

disbelieve

From apistos; to be unbelieving, i.e. (transitively) disbelieve, or (by implication) disobey -- believe not.

see GREEK apistos

Cognate: 569 apistéō (from 571 /ápistos, "unfaithful," without faith, i.e. negating 4103 /pistós, "faithful") – properly, refusing to be persuaded by God ("betray His trust," J. Thayer).

569 /apistéō ("not willing to be persuaded") means more than "disbelieve" ("not believing") because it indicates "refusing to be faithful" (honor a trust or revelation from the Lord). See 571 (apistos).

569/apisteō ("refuse to be persuaded") is sin committed by believers (Mk 16:11; Lk 24:11,41) and unbelievers (Ac 28:24; Ro 3:3; 1 Pet 2:7). 569 (apistéō) reveals a person is unconvinced when they should be persuaded by what the Lord has done (offered).

Word Origin
from apistos
Definition
to disbelieve, be faithless
NASB Translation
believe (3), disbelieve (1), disbelieved (1), faithless (1), refused to believe (1), would not believe (1).

STRONGS NT 569: ἀπιστέω

ἀπιστέω, ἀπίστω; (imperfect ἠπίστουν); 1 aorist ἠπίστησα; (ἄπιστος);

1. to betray a trust, be unfaithful: 2 Timothy 2:13 (opposed to πιστός μένει); Romans 3:3; (others deny this sense in the N. T.; cf. Morison or Meyer on Romans, the passage cited; Ellicott on 2 Timothy, the passage cited).

2. to have no belief, disbelieve: in the news of Christ's resurrection, Mark 16:11; Luke 24:41; with dative of person, Luke 24:11; in the tidings concerning Jesus the Messiah, Mark 16:16 (opposed to πιστεύω) (so 1 Peter 2:7 T Tr WH); Acts 28:24. (In Greek writings from Homer down.)

Definition and Scope

The verb refers to an active refusal to believe, an unwillingness to entrust oneself to a testimony or promise. Scripture portrays this posture as culpable, never neutral, because it rejects divinely given evidence and offers.

Occurrences in the New Testament

• Mark 16:11; 16:16
• Luke 24:11; 24:41
• Acts 28:24
• Romans 3:3
• 2 Timothy 2:13
• 1 Peter 2:7

Unbelief and the Resurrection Witness

Within the resurrection narratives the word highlights the disciples’ initial doubt in spite of clear testimony. “And when they heard that Jesus was alive and she had seen Him, they did not believe it” (Mark 16:11). The same resistance reappears in Luke 24:11 and 24:41. These scenes stress that faith is not generated by empirical evidence alone; it springs from a heart opened by God to what He has already certified (Luke 24:45).

Unbelief and Eternal Destiny

Mark 16:16 sets the most sobering contrast: “Whoever believes and is baptized will be saved, but whoever does not believe will be condemned.” The verb therefore marks a decisive boundary between salvation and judgment, linking unbelief to personal culpability and irrevocable loss.

Unbelief Among the Covenant People

Romans 3:3 addresses Israel’s failure to trust God’s covenant faithfulness: “Will their unfaithfulness nullify God's faithfulness?” The answer is emphatically no, underscoring that God’s promises stand even when some within His covenant community refuse to believe. Acts 28:24 reveals a similar pattern when Paul preaches in Rome: “Some were convinced by what he said, but others refused to believe.” The unbelief does not negate God’s plan; it merely exposes hardened hearts.

Unbelief and Divine Faithfulness

Paul consoles believers in 2 Timothy 2:13: “If we are faithless, He remains faithful, for He cannot deny Himself.” Human unfaithfulness never alters the character of God; His constancy secures the church even when individuals falter.

Christ the Cornerstone Rejected

Peter applies Psalm 118 to Christ: “To you who believe, then, this stone is precious. But to those who do not believe, ‘The stone the builders rejected has become the cornerstone’” (1 Peter 2:7). Unbelief fulfills prophecy by rejecting the very foundation God has laid for salvation, yet that rejection cannot derail God’s redemptive design.

Historical-Theological Reflection

Early Christian preaching faced entrenched skepticism both inside Judaism and among Gentiles. The repeated use of this verb in Acts and the Epistles illustrates how the gospel confronted resistance and how the apostolic writers interpreted such resistance—as fulfillment of Scripture and as a call to persistent evangelism.

Pastoral and Evangelistic Application

1. Preaching must present Christ’s resurrection as historical fact while appealing for Spirit-wrought faith.
2. Believers should rest in God’s faithfulness even when confronted with personal lapses or widespread apostasy.
3. Evangelists can expect mixed responses; unbelief does not signal failure but invites continued testimony and prayer.
4. Congregations must guard against the subtle drift from belief to unbelief, remembering that refusal to trust divine revelation carries eternal consequences.

Summary

Across its eight New Testament occurrences, the verb exposes the moral gravity of rejecting God’s testimony while highlighting the unwavering faithfulness of God and the unassailable triumph of His redemptive plan in Jesus Christ.

απιστησας απιστήσας ἀπιστήσας απιστουμεν απιστούμεν ἀπιστοῦμεν απιστουντων απιστούντων ἀπιστούντων απιστουσιν ἀπιστοῦσιν ηπιστησαν ηπίστησαν ηπίστησάν ἠπίστησαν ἠπίστησάν ηπιστουν ηπίστουν ἠπίστουν apistesas apistēsas apistḗsas apistoumen apistoûmen apistounton apistountōn apistoúnton apistoúntōn apistousin apistoûsin epistesan epístesan epístesán ēpistēsan ēpístēsan ēpístēsán epistoun epístoun ēpistoun ēpístounInterlinear Greek • Interlinear Hebrew • Strong's Numbers • Englishman's Greek Concordance • Englishman's Hebrew Concordance • Parallel Texts