2. The Adjective The Greek adjective apistos, occurring 23x in the NT, a compound of the negative prefix and pistos [faithful, reliable], refers to that which is “(1) unbelievable, incredible; (2) without faith, disbelieving, unbelieving” [BDAG].

3. The Verb The verb apisteō, occurring 8x, derived from apistos, means “(1) disbelieve, refuse to believe; (a) generally; (b) in description of response to a deity or divine activity or to reports about divine activity; (2) not believe in someone; (3) be unfaithful of one lacking a sense of obligation” [BDAG].

4. The Noun The noun apistia, occurring 11x, derived from apistos, signifies an “(1) unwillingness to commit oneself to another or respond positively to the other’s words or actions, lack of belief, unbelief; (2) lack of commitment to a relationship or pledge, unfaithfulness” [BDAG].

5. Usage in the Gospels Eleven of the thirteen occurrences center around three events: the unbelief of the inhabitants of Nazareth in rejecting the ministry of Jesus; the unbelief of the disciples in their failure to cast out the demonic, and the unbelief of the disciples in rejecting the testimony of those who had seen the risen Savior. These examples reveal that unbelief is self-defeating, ineffective, and also hardhearted and callous.

6. Unbelief is Self-Defeating The inhabitants of Nazareth reveal that unbelief is self-defeating (Matt. 13:53-58; Mark 6:1-6).

7. Unbelief is Ineffective The failure of the disciples and the father of the demonic reveal that unbelief is ineffective (Matt. 17:14- 21; Mark 9:14-29; Luke 9:37-43).

8. Unbelief is Callous In rejecting the testimony of those who had seen the risen Savior, the disciples reveal that unbelief is callous and hard-hearted (Mark 16:9-14; Luke 24:1-11, 36-49; John 20:19-29).

9. Conclusion Avoiding the instability of doubt and unbelief, let us grow up in all aspects into Him who is the head, even Christ (Eph. 4:11-16; James 1:5-8).