Mencius - Book 4, Part 2, Chapter 14

Mencius said, 'The superior man makes his advances in what he is learning with deep earnestness and by the proper course, wishing to get hold of it as in himself. Having got hold of it in himself, he abides in it calmly and firmly. Abiding in it calmly and firmly, he reposes a deep reliance on it. Reposing a deep reliance on it, he seizes it on the left and right, meeting everywhere with it as a fountain from which things flow. It is on this account that the superior man wishes to get hold of what he is learning as in himself.'
~ James Legge translation via nothingistic.org ~

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