Exodus 16:4
Then said the LORD unto Moses, Behold, I will rain bread from heaven for you; and the people shall go out and gather a certain rate every day, that I may prove them, whether they will walk in my law, or no.
Exodus 20:20
And Moses said unto the people, Fear not: for God is come to prove you, and that his fear may be before your faces, that ye sin not.