The same applies if, by mentioning voice, the oath-taker means affirming the reports from the Prophet (may Allah bless him and grant him peace), his Companions, and their followers which accord with the Quran and were accepted by the early generations. These include the report from the Prophet (may Allah bless him and grant him peace) recorded by al-Bukhārī and Muslim in their Sahīh collections:
“Allah calls to Adam with a voice.”
They also include the report cited by al-Bukhārī as evidence on this subject:
“Allah calls to His servants on the Day of Resurrection with a voice heard by those far away just as it is heard by those nearby.”
And the report:
“When Allah speaks revelation—whether the Quran or something else—the inhabitants of the heavens hear His voice.”
In the wording of Ibn Abbās: “They heard the voice of the Compeller.” There is also the report that Allah spoke to Moses with a voice.
These and other reports were stated—either in their own words or as transmissions from others—by such figures as Abd Allāh ibn Masʿūd, Abd Allāh ibn Abbās, Abū Hurayra, Abd Allāh ibn Unays, Jābir ibn Abd Allāh, Masrūq, one of the foremost senior scholars among the Successors, Abū Bakr ibn Abd al-Rahmān ibn al-Hārith ibn Hishām, one of the seven jurists, Ikrima, the freedman of Ibn Abbās, al-Zuhrī, Ibn al-Mubārak, Ahmad ibn Hanbal, and countless others.
No scholar of Islam before the second century is reported to have denied this or maintained the contrary. Rather, these reports were well known among them and circulated in every age and region. Someone did, however, deny this during the time of Imam Ahmad; this was the first period in which innovations arose denying this in opposition to the scriptural texts. Otherwise, individuals who denied this and other matters had already appeared before him, but the Muslims shunned such a person for as long as he denied this, and he became among them like a mangy camel.
Thus, if the oath-taker intended what has been authentically transmitted from the early generations, he has not broken his oath.