Аль-Бакара 2:57

These two incidents took place in the wilderness of Tih. The Israelites belonged to Syria, but had gone to Egypt in the time of Sayyidna Yusuf (علیہ السلام) (Joseph), and settled there, while Syria itself had come under the domination of a people called the ` Amaliqah (Amaleks). When the Pharaoh had been drowned and the Israelites could live in peace, Allah commanded them to go to war against the ` Amaliqah, and to free their homeland. The Israelites started on the expedition, but, on approaching Syria, when they came to learn about the military strength of the foe, their courage failed them, and they refused to engage themselves in the Jihad. Allah punished them for their disobedience, so that for full forty years they kept wandering about in a wilderness, and could not even go back to Egypt. The wilderness was not very vast, but only a stretch of some ten miles, lying between Egypt and Syria. They would make a day-long march in the direction of Egypt, and stop somewhere for the night. But, on getting up the next morning, they would always find themselves just where they had started from. Thus, they spent forty years wandering about in the wilderness in futile rage and exasperation. That is why the wilderness is called Tih تیہ ، which signifies 'having lost one's way'.

The wilderness was just a barren space without a tree or a building which could offer protection against heat or cold. There was no food to eat, and no clothes to wear. But in answer to the prayer of Sayyidna Musa (علیہ السلام) ، Allah made a miraculous provision for all their needs. When they could not bear the scorching sun, Allah sent them the shade of a thin, white cloud. When they began to starve, Allah blessed them with Mann مَن (manna) and Salwa سلوا . That is to say, Allah produced honeydew in abundance which they could easily gather. Hence it has been designated as mann مَن which signifies "a gift or favour". Then, quails would not flee but come around them, so that they could catch the birds with little effort. The two things being unusual, the Holy Qur'an says that Allah made them "descend" for the benefit of the Israelites. Similarly, when they were thirsty, Allah commanded Sayyidna Musa (علیہ السلام) to strike a rock with his staff, which made twelve streams gush forth, as the Holy Qur'an narrates in another place. When they complained of the thick darkness of the night, Allah produced for them a constant pillar of light. When their clothes began to wear out, Allah showed another miracle - their clothes would neither go dirty nor wear out, while the clothes of the children grew with their growth. (Qurtubi)

Allah had commanded the Israelites to take as much of the miraculous food as they really needed, and not to store it for future use. But when they disobeyed this commandment, the meat began to rot. This is how they harmed, not Allah, but themselves.