Acts 22:9

And they that were with me beheld indeed the light, but they heard not the voice of him that spake to me.

Heard not the voice ... This is actually a mistranslation and should be rendered, "They understood not the voice."[11] Heard, which of course is in the Greek, is, however, an idiom, frequently used for "understood" or even for "understood and obeyed."[12]

The New Testament usage of the word "hear" and its derivatives is apparent from this: "He that speaketh in a tongue speaketh not unto men, but unto God; for no man heareth" (1 Corinthians 14:2), meaning, of course, simply that "no man understands what is being said." We have exactly the same meaning here, as proved by "hearing the voice, but beholding no man" (Acts 9:7).

McGarvey said, "It is common among all classes of men to say (of a speaker) I did not hear, not meaning they could not hear the sound of the speaker's voice, but that they could not hear what he said."[13]

[11] Alexander Campbell, Acts of Apostles (Austin, Texas: Firm Foundation Publishing House), p. 148.

[12] Ibid.

[13] J. W. McGarvey, Commentary on Acts (Cincinnati, Ohio: Standard Publishing Company), 2p. 216.