The Greek word apisteo

Found only in Mk. 16:11, 16; Lk. 24:11, 41; Acts 28:24; Rom. 3:3; 2 Tim. 2:13; 1 Pet. 2:7, the Greek verb “apisteo” meant “believe not” “disbelieve,” or “betray a trust.”  The “alpha” (“a”) at the beginning of this word is similar to our adding the letter “a” to the word “theist” (i.e. theist—a believer in God—is instantly changed into the word atheist—someone who does not believe in God).

Some of the Lord’s disciples did not believe He had been raised from the dead (Mk. 16:11; Lk. 24:11).  People who refuse to believe (Mk. 16:16) will be condemned to hell.  The things of God are sometimes believed and sometimes not (Acts 28:24; Rom. 3:3; 1 Pet. 2:7), but God is always faithful (2 Tim. 2:13).