“Kind speech” means that when you see sentient beings, you arouse the heart of compassion and offer words of loving care. it is contrary to cruel or violent speech.
In the secular world, there is the customer of asking after someone’s health. In the Buddha way, there is the phrase “Please treasure yourself” and the respectful address to seniors “May I ask how you are?”. It is the kind speech to speak to sentient beings as you would to a baby.
Praise those with virtue; pity those without it. If kind speech is offered, little by little kind speech expands. Thus, even kind speech that is not ordinarily known or seen comes into being. Be willing to practice it for this entire present life; do not give up, world after world, life after life. Kind speech is the basis for reconciling rulers and subduing enemies. Those who hear kind speech from you have a delighted expression and joyful mind. Those who hear of your kind speech will be deeply touched; they will always remember it.
Know that kind speech arises from kind heart, and kind heart from the seed of compassionate heart. Ponder the fact that kind speech is not just praising the merit of others; it has the power to turn the destiny of the nation.
Even when you are clearly correct and others are mistaken, it is harmful to argue and to defeat them. On the other hand, if you admit fault when you are right, you are a coward. It is best to step back, neither trying to correct others nor conceding to mistaken views. If you don’t react competitively, and let go of the conflict, others will also let go of without harboring ill will. Above all, this is something you should keep in mind.
— Dogen Zenji