To speak kindly does not hurt the tongue.
— Proverbs

Think not those faithful who praise all thy words and actions, but those who kindly reprove thy faults.
Socrates kindly quote

I thoroughly disapprove of duels. If a man should challenge me, I would take him kindly and forgivingly by the hand and lead him to a quiet place and kill him.
— Mark Twain

A guest never forgets the host who had treated him kindly.
— Homer

Be generous with kindly words, especially about those who are absent.
— kindly quotation by Johann Wolfgang von Goethe