لَا تُزْرِمُوهُ
Do not interrupt him abruptly.
دَعُوهُ
Leave him for the moment.
The first expression uses prohibitive lā with a present-tense verb; the second is a command. Together they direct the Companions away from an immediate interruption.
إِنَّمَا هِيَ لِذِكْرِ اللَّهِ uses innamā to emphasize the mosque’s proper purpose. Grammar helps explain what the instruction actually required.