«فَقَالَ: هَذَا أَبُو زَيْدٍ السَّرُوجِيُّ»
He replied: This is Abū Zayd al-Sarūjī.
The declarative sentence reveals the stranger as Abū Zayd al-Sarūjī. Grammatically the demonstrative begins the predication; literarily the delayed timing of that information makes the earlier sermon and donations look different.
Al-Ḥārith can report what was seen and heard, not automatically every hidden intention. The revelation makes readers reassess prior events. Distinguish narrator knowledge, a speaker’s self-description and what events corroborate.