There’s a really interesting verse in Proverbs 24:26; it says “an honest answer is like a kiss on the lips." This is the only time that a “kiss on the lips” is mentioned in the entire Bible, but it doesn’t necessarily point to what you think. 

In Middle Eastern culture, when one man met another, you could easily tell if they were equals because they would kiss on the lips. Now if there was a small difference between the two men, the lesser would kiss the cheek of the greater one. And if there was a big difference between the two, the lesser would bow before the man who was considered greater. 

So for you to give an honest answer, for you to speak to another person without cursing them, you need to come at it from their level. You’re to consider how they best receive encouragement and criticism. If they’re a more logical, analytical type, you might approach them differently than if they’re wired more emotionally.