Mencius - Book 2, Part 2, Chapter 14

When Mencius left Ch'î, he dwelt in Hsiû. There Kung-sun Ch'âu asked him, saying, 'Was it the way of the ancients to hold office without receiving salary?'

Mencius replied, 'No; when I first saw the king in Ch'ung, it was my intention, on retiring from the interview, to go away. Because I did not wish to change this intention, I declined to receive any salary.

'Immediately after, there came orders for the collection of troops, when it would have been improper for me to beg permission to leave. But to remain so long in Ch'î was not my purpose.'
~ James Legge translation via nothingistic.org ~

Go here to read the introductory post to this serialized version of the Works of Mencius.