Mencius - Book 5, Part 1, Chapter 5A

Wan Chang said, 'Was it the case that Yâo gave the throne to Shun?' Mencius said, 'No. The sovereign cannot give the throne to another.'

'Yes; but Shun had the throne. Who gave it to him?' 'Heaven gave it to him,' was the answer.

'" Heaven gave it to him:" did Heaven confer its appointment on him with specific injunctions?'

Mencius replied, 'No. Heaven does not speak. It simply showed its will by his personal conduct and his conduct of affairs.'
~ James Legge translation via nothingistic.org ~

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