Teaching is generosity with consequences that can outlive both people involved.
STILLNESS
STILLNESS
What you teach someone can be taught again by them, and again by whoever they teach, long after both of you are gone. That makes it one of the few kinds of generosity with no natural endpoint. It also means the care you take in how you teach matters, since errors travel just as well as accuracy.
Be as accurate as you can with what you pass on, and say where you are unsure. Then let it go. What happens to it afterwards is not yours to control.
What have you taught that has already been passed on again?
Free, with nothing to buy inside it.