An uncertain voice (αδηλον φωνην). Old adjective (α privative, δηλος, manifest). In N.T. only here and Luke 11:44. Military trumpet (σαλπιγξ) is louder than pipe or harp.

Shall prepare himself (παρασκευασετα). Direct middle future indicative of παρασκευαζω, old verb, in N.T. only here, 2. Corinthians 9:2; Acts 10:10. From παρα, σκευη(preparation).