Why can “matā naḥkumu? — baʿda al-faḥṣi” illustrate ellipsis?

Supplementary Practice 13: Attribution, Quotation and Evidential Restraint in Rhetorical Analysis

• Semantic condensation with no recoverable omitted element
• The verb naḥkumu is recoverable from the question
• An independent statement with baʿda as an ordinary subject
• A qualification that bars all judgments permanently