This chapter taken from the Tao Te Ching can be quoted as an appreciation of all good and kind teachers on earth:
Sincere words are not fine, fine words are not sincere.
Those who are skilled (in the Tao) do not dispute (about it); the disputatious are not skilled in it.
Those who know (the Tao) are not extensively learned; the extensively learned do not know it.
The sage does not accumulate (for himself). The more that he expends for others, the more does he possess of his own; the more that he gives to others, the more does he have himself.
The Way of Heaven is to benefit, not to harm. The Way of the Sage is to do his duty, not to strive with anyone. [Wu]
[TTC 81, James Legge.]