The Messenger of Allah ﷺ said, "The best among you are those with the finest character." The Prophet ﷺ was neither vulgar nor one who spoke obscenely.
حدثنا محمود بن غيلان حدثنا أبو داود قال أنبأنا شعبة عن الأعمش قال سمعت أبا وائل يحدث عن مسروق
قال رسول الله ﷺ خياركم أحاسنكم أخلاقا ولم يكن النبي ﷺ فاحشا ولا متفحشا
Agreed upon by Bukhari and Muslim. Bukhari narrated it in the Book of Virtues, Chapter on the Description of the Prophet, hadith no. 3559, and Muslim, hadith no. 2321, from the hadith of Amash with this wording. It is also found in Musnad Abu Dawud Tayalisi, hadith no. 2246, with a similar meaning.