Hadith on Speech: Speak as you like to be spoken to

Harmalah ibn Abdullah reported: I said, “O Messenger of Allah, what do you command me to do?” The Messenger of Allah, peace and blessings be upon him, said, “O Harmalah, do what is good and avoid what is evil. Consider what you are pleased to hear people say to you; when you stand to leave them, behave this way. Consider what you dislike to hear people say to you; when you stand to leave them, avoid doing it.” When I went back, I reflected on it and found that these two sayings did not leave anything out.

Source: al-Adab al-Mufrad 215

Grade: Hasan (fair) according to Al-Suyuti

عَنْ حَرْمَلَةَ بْنِ عَبْدِ اللَّهِ قُلْتُ يَا رَسُولَ اللَّهِ مَا تَأْمُرُنِي أَعْمَلُ قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ يَا حَرْمَلَةُ ائْتِ الْمَعْرُوفَ وَاجْتَنَبِ الْمُنْكَرَ وَانْظُرْ مَا يُعْجِبُ أُذُنَكَ أَنْ يَقُولَ لَكَ الْقَوْمُ إِذَا قُمْتَ مِنْ عِنْدِهِمْ فَأْتِهِ وَانْظُرِ الَّذِي تَكْرَهُ أَنْ يَقُولَ لَكَ الْقَوْمُ إِذَا قُمْتَ مِنْ عِنْدِهِمْ فَاجْتَنِبْهُ فَلَمَّا رَجَعْتُ تَفَكَّرْتُ فَإِذَا هُمَا لَمْ يَدَعَا شَيْئًا

215 الأدب المفرد للبخاري

28 المحدث السيوطي خلاصة حكم المحدث حسن في الجامع الصغير