What was the purpose of the test of the manna, and the general purpose of testing Am Yisrael throughout their journeys in the desert? God's causing of hardship to Israel should be understood as part of a process of education, as part of a process of building the religious virtue of awe and fear of heaven. It is intended to benefit Israel and help them, both now and in the future in following God's word and fidelity to his commandments.

Testing Am Yisrael
Divine Tests