مَا أَثْبَتْنَا النِّسْبَةَ، وَإِنَّمَا طَلَبْنَا مُقَارَنَةَ النُّسَخِ؛ فَالْعِلْمُ أَمَانَةٌ.
We did not establish the attribution; we asked only for comparison of the copies, for knowledge is a trust.
The statement first rejects a falsely ascribed claim, then limits the actual request, and finally reinforces the position by a general principle. Each part answers a specific need in the preceding exchange. Without a mistaken accusation the opening denial would have a different purpose; with a different audience the final maxim might also work differently.
A defensible rhetorical analysis proceeds in four steps: (1) identify the proposition, (2) parse the clause structure, (3) determine the listener's question or possible misconception, and (4) state the contextual evidence for every technical classification.