Salaam/peace
The Shade, the Manna and the Quail
(And We shaded you with clouds) "This happened when they were in the desert and the clouds shielded them from the sun.''
Ibn Jarir said that several scholars said that the type of cloud the Ayah mentioned, "was cooler and better than the type we know.''
[وَأَنزَلْنَا عَلَيْكُمُ الْمَنَّ]
And sent down on you Al-Manna, The manna used to descend to them to the trees, and they used to eat whatever they wished of it.
…..The manna, which was whiter than milk and sweeter than honey, used to rain down on the Children of Israel, just as the snow falls, from dawn until sunrise. One of them would collect enough for that particular day, for if it remained more than that, it would spoil.
On the sixth day, Friday, one would collect enough for the sixth and the seventh day, which was the Sabbath during which one would not leave home to seek his livelihood, or for anything else. All this occurred in the wilderness.
The type of manna that we know provides sufficient food when eaten alone, because it is nutritious and sweet. When manna is mixed with water, it becomes a sweet drink. It also changes composition when mixed with other types of food.
However, this is not the only type. The evidence to this fact is that Al-Bukhari narrated, that Sad bin Zayd said that the Messenger of Allah said,
«الْكَمْأَةُ مِنَ الْمَنِّ وَمَاؤُهَا شِفَاءٌ لِلْعَيْن»
(Kam'ah (truffles) is a type of manna, and its liquid is a remedy for the eyes.)
…………….. "The (Salwa) is a bird that looks like the quail………………… Also, `Ikrimah said that the Salwa is a bird in Paradise about the size of a sparrow.
….During that time, an Israelite could catch as many quails as was sufficient for that particular day, otherwise the meat would spoil.
On the sixth day, Friday, he would collect what is enough for the sixth and the seventh day, the Sabbath, during which one was not allowed to depart his home to seek anything.''
Allah said,
[كُلُواْ مِن طَيِّبَـتِ مَا رَزَقْنَـكُمْ]
Eat of the good lawful things We have provided for you, (7:160) this form of command is a simple order of allowance, guiding to what is good. Allah said,
[وَمَا ظَلَمُونَا وَلَـكِن كَانُواْ أَنفُسَهُمْ يَظْلِمُونَ]
(And they did not wrong Us but they wronged themselves) means, `We commanded them to eat from what We gave them, and to perform the acts of worship (but they rebelled).' This Ayah is similar to Allah's statement,
[كُلُواْ مِن رِّزْقِ رَبِّكُمْ وَاشْكُرُواْ لَهُ]
Eat of the provision of your Lord, and be grateful to Him (34:15).
Yet, the Children of Israel rebelled, disbelieved and committed injustice against themselves, even though they saw the clear signs, tremendous miracles and extraordinary events.
Tafsir Ibn Kathir
http://www.tafsir.com/Default.asp