Sent to the worst tyrant with an instruction about tone
Mūsā and Hārūn were told how to speak before they were told what to say.
فَقُولَا لَهُۥ قَوْلًا لَّيِّنًا لَّعَلَّهُۥ يَتَذَكَّرُ أَوْ يَخْشَىٰ
Fa-qūlā lahu qawlan layyinan laʿallahu yatadhakkaru aw yakhshā.
And speak to him with gentle speech that perhaps he may be reminded or fear [Allāh]."
The man being spoken about had claimed to be a god and was killing children. The instruction was still: speak gently.
Source
The Qur'an · 20:44
Qur'an
- Qur'anic text in the Uthmani script via Quran.com; translation: Saheeh International