Sufyan ath-Thawri said, “Only someone with three qualities may command what is right and forbid what is wrong; that he is gentle in his commanding and gentle in his forbidding, that he is fair and just in his commanding and fair and just in his forbidding, that he has knowledge of what he commands and knowledge of what he forbids.”
Ahmad said, “People need encouraging persuasiveness and gentleness in commanding what is right without being hard or stern except for the man who openly does immoral actions, for he is due no respect.” He said, “When the companions of Ibn Mas’ud used to pass by some people whom saw doing something they deplored , then they would say, ‘Gentle! may Allah show mercy you mercy. Gentle may Allah show you mercy'”
Ahmad said ” One must command gently and with humilty, so that if they make him hear what he dislikes then he will not become angry and so wish to try and avenge himself.
“The Compendium of Knowledge and Wisdom (Jami’ Al-Ulum wal Hikam)
Ibn Rajab Al-Hanabali translated by Abdassam Clarke p560