An objection alleges a circle (dawr) if prophetic truthfulness is established by the prophet's report, while the report's truthfulness is in turn established by divine speech. A vicious circle arises when each proposition requires the other with no independent starting point.
The reply distinguishes the evidence establishing prophethood from reports accepted after that establishment. Evidence from a miracle may independently support the messenger's truthfulness, after which the messenger's report concerning divine speech is received.
The issue is the order and independence of proof, not merely repeating the conclusion in a premise.