وَإِمْلَاءُ الْخَيْرِ خَيْرٌ مِنَ السُّكُوتِ values useful speech—teaching, sound advice, and communicating what is good—above silence. وَالسُّكُوتُ خَيْرٌ مِنْ إِمْلَاءِ الشَّرِّ prefers silence over speech that spreads harm, falsehood, or wrongdoing.
إِمْلَاء can mean dictation or expressing words; in this context it refers to conveying good or evil speech.
Clarifying a misunderstanding with accurate, gentle words is beneficial. Repeating an unverified accusation is harmful. The difference lies in truth and effect, not in the amount of speech.