وَهُمْ مَعْصُومُونَ عَنِ الْكَذِبِ خُصُوصًا فِيمَا يَتَعَلَّقُ بِأَمْرِ الشَّرَائِعِ
They are protected from falsehood, especially in transmitting divine legislation.
Intentionally attributing false information to God or changing revealed duties would undermine the credibility of prophetic instruction. Accordingly, deliberate falsehood in the delivery of revelation is excluded as a foundational principle of the office.
Example: If the messenger could knowingly reverse a divine command, the hearer could not reliably identify what God had required. Protection of truthful transmission addresses precisely that danger.