The Holy Quran 31:19 — Surah Luqman
Arabic text
وَٱقْصِدْ فِى مَشْيِكَ وَٱغْضُضْ مِن صَوْتِكَ ۚ إِنَّ أَنكَرَ ٱلْأَصْوَٰتِ لَصَوْتُ ٱلْحَمِيرِ
Translation
"Moderate your walk (be calm, composed and modest) and lower your voice (speak gently to people). Indeed, the most hateful sound is the braying of a donkey (which ends in a high pitch that grates one's ears. People should therefore avoid speaking in this manner)."
Tafsir (excerpt) — Tafsir Usmani
Moderation in speech: that is, adopt a gait of humility, gravity and moderation; do not speak without need, and when speaking, do not shout beyond limits. If speaking in a loud voice were any merit, then think of the voice of the donkey: it brays very loudly, yet how ugly and harsh it is!
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