Notes from Suzuki’s great compendium of zen..

Monk: I understand that when a lion seizes upon his opponent, whether it is a hare or an elephant, he makes an exhaustive use of his power; pray tell me what is this power?

Master: The spirit of sincerity.
Sincerity, that is, not-deceiving, means ‘putting forth one’s whole being,’ technically known as ‘the whole being in action’… in which nothing is kept in reserve, nothing is expressed under disguise, nothing goes into waste. When a person lives like this, he is said to be a golden-haired lion; he is the symbol of virility, sincerity, whole-heartedness; he is divinely human.

(From the book written by Ruth Benedict)