Prophet Muḥammad Ṣallallāhu-ʿAlaihi Wa Sallam said:
“Speak the truth EVEN if it’s BITTER (i.e. difficult to admit).”
● [صحيح الترغيب والترهيب رقم الحديث ٢٢٣٣ ، صححه الألباني]
قلت يا رسول الله قال قل الحق وإن كان مرا
[Ibn Hibban graded it Sahih (authentic) as a part of a long Hadith}
Also in Bulugh Al Maram 7/132, Ibn Hibban 449 & 361, and Sahih Targhib wa Tarhib 4866
Grade: Sahih li ghayrihi (authentic due to external evidence) according to Al-Albani
Sh. Ibn ʿUthaymeen Raḥimahullāh said in its Sharḥ:
“Speak (قل) here is an imperative verb which makes it a command that is *OBLIGATORY* upon us [..] likewise the opposite of that is also obligatory i.e do not speak with falsehood even if it is sweet (easy).”
● [بلوغ المرام ١١٠]