Simak ibn Ḥarb, from Jābir ibn Samurah, who said—­and he narrated the report in full.
It is also found in the Musnad and in the Sunan of Abū Dāwūd, and through several other abbreviated chains from Simak; it may be cited again under the discussion of the iqāmah.

His wording “lā yukhrim” (“he never missed”) is explained in Nayl al-Awṭār as meaning: he omitted nothing of its phrases. That explanation is plausible, yet the stronger view in my opinion is that “lā yukhrim” means that he neither shortened the call nor delayed it beyond its proper time, namely the moment the sun passes the meridian. The proof is the second half of the ḥadīth, for it states that Bilāl would postpone the iqāmah until the Prophet ﷺ came out.

I later found corroboration for this in a narration recorded by al-Ṭayālisī: Qays related to us from Simak ibn Ḥarb, from Jābir, who said:
“Bilāl would pronounce the adhān when the sun had just begun to decline. At times he would delay the iqāmah a little, and at times advance it slightly, but the adhān he never failed to give at its appointed time.”

This text clearly supports the position we have preferred, and Allah knows best.
The ḥadīth therefore teaches that the adhān for Ẓuhr must be made exactly when the time enters, without being advanced or delayed; the same applies to all the prayers except Fajr, as noted earlier.

14 – Whoever hears the call is required to do several things:
First: to repeat what the muʾadhdhin says.
There are several ḥadīths on this point: