The Israelites departed the Sinai Desert, where they had been encamped since the giving of the Torah, and start journeying towards the Promised Land.
And the problems begin almost immediately. First they complain about the length of the "arduous" journey (three days!), and then, for lack of anything substantive to grumble about, they gripe about the miraculous and extremely tasty Manna. This form of testing G‑d wasn't new; it had actually become fairly standard behavior. Altogether, the Jews tested G‑d ten times before He disgustedly declared the entire generation unworthy of entering the Holy Land.
Ironically, the Jews seemed to be following G‑d's example. The Mishna (Ethics 5:3) says that "with ten tests our father Abraham was tested [by G‑d] and he withstood them all—in order to make known how great was our father Abraham's love [for G‑d]." This raises the question: isn't this a tad hypocritical on G‑d's part? If it is acceptable for G‑d to test Abraham, why was it not appropriate for the Jews to reciprocate in kind? If He can dish it out, shouldn't He be able to take it as well?!
G‑d’s tests are actually a demonstration of trustIn truth, however, there is a fundamental difference between the Jews testing G‑d and G‑d's testing of Abraham. G‑d's tests are intended to uncover within an individual hidden powers which would otherwise be untapped. Abraham always had the courage, fortitude and love for G‑d necessary to sacrifice his son, however, neither he nor the world was cognizant of this latent potential until G‑d actually put him to the test. G‑d only tests a person who has the powers to withstand the tribulation, thus G‑d's tests are actually a demonstration of trust; G‑d only tests a person whom He trusts to have the ability to pass the test with flying colors. The Jews, on the other hand, tested G‑d because they lacked trust in their Creator. If they would have trusted G‑d they would have realized that all His actions were in their best interests and He would surely provide for their every need.
This is a powerful lesson for us all. When faced with difficulty and challenges we must keep in mind that this is actually a display of trust on G‑d's part. We must live up to G‑d's high expectations, and then the test will have outlived its purpose and will vanish.