ואל משה אמר, And He had said to Moses (previously), etc. It appears that this paragraph was revealed immediately after the revelation at Mount Sinai but was inserted in the Torah only here. There is no point in citing numerous arguments proving this theory. Ibn Ezra, Nachmanides, and Rashbam are all agreed that the paragraph must have been revealed at the time of the revelation.

I have seen an undisputed theory in the Mechilta according to which Moses built an altar on the fifth day of Sivan (a day before the revelation) and that this was the altar mentioned in verse 4, and that he concluded a covenant with the people confirming their adherence to the seven Noachide laws as well as to the statutes he had taught the people at Marah (15,25). Some rabbis hold that the covenant Moses made the people swear to at that time covered all the laws revealed in the Torah till the end of the Book of Leviticus. According to these sages all those laws had to be revealed before the revelation at Mount Sinai. Seeing the people had not been asked to enter into a covenant concernig any of G'd's laws prior to this, we must assume that Moses tested them to see if they were willing to enter into such a covenant of their own free will concerning all of the commandments which had already been revealed even though it had not been G'd Himself who had given them these commandments. Perhaps we find a hint of all this in G'd telling Moses in 19,3:"and tell the children of Israel!" Shabbat 86 understands this directive to mean that Moses was to illustrate the legislation to the people by employing parables and other homiletical material to make these laws appear acceptable in their eyes. As a result of clever presentation of all these laws the people would be prepared to swear an oath obligating themselves to observe all of these commandments. The statement in Shabbat 86 that the Israelites did not say: "we will listen and do," but: "we will do and listen," was the outcome of their each having been "crowned" by 600,000 angels. All these comments prove that our paragraph refers to events prior to the giving of the Torah.

ואל אצילי בני ישראל לא שלח ידו, And G'd did not lay a hand on the nobles of the children of Israel; Why did the Torah have to make mention of ואל אצילי בני ישראל? If the Torah had merely written: "He did not lay a hand on them," I would have known already that the subject of the verse are the elders who were mentioned in the previous verse. Perhaps the Torah wanted us to know that the reason why G'd did not lay a hand on these people at that time was that they were "the nobles of the children of Israel." Alternatively, G'd did not want to spoil the prevailing spiritual high and joy of the people by killing so many of their leaders at that time and causing them to be mourned (compare Bamidbar Rabbah 15).

לא שלח ידו…ויאכלו, He did not lay a hand;…they ate, etc. Why did the Torah mention once more ויחזו and was not content with the words ויראו? Our sages in Vayikra Rabbah 20,10 claim that these people feasted by means of their vision of G'd, ויחזו. Their very visual experience provided the kind of satisfaction for them that ordinary people under normal circumstances experience as the result of consuming food and drink. This still does not provide an adequate explanation for the fact that the verse reports what G'd did not do as a consequence of an activity by these people which had not even been described. The Torah should have mentioned the eating and drinking before mentioning G'd's reaction or apparent lack of reaction, i.e. His patience in deferring punishment. At any rate, the word ויחזו is quite superfluous even after the explanation of the Midrash.

Perhaps we must understand the Torah's intention by referring to Exodus 33,23 where G'd speaks about removing his "palm" in order for Moses to see His "back" instead of His "face." At that point G'd made it clear that even someone on Moses' spiritual level who had experienced G'd's presence revealing Himself as no other mortal before or after him, had to be prevented from beholding G'd's face. G'd inserted a divider between Himself and His face. In our verse the Torah reveals that G'd did not insert such a divider between Himself and the vision of these אצילי בני ישראל, "nobles of the children of Israel," because they were אצילים. He permitted them to feast their eyes on this vision.

We have to understand the whole verse as follows: "They saw the G'd of Israel," i.e. they saw a great light symbolising the G'd of Israel, but they only looked at what was beneath His feet. Seeing that G'd had not laid a hand on them for doing so, i.e. He had not taken measures to deny them this vision, they now indulged in ויחזו, an intensified look, something which provided them with the kind of satisfaction ordinary people get through the intake of food and drink.

You must not wonder why these people were allowed a vision which was even denied to Moses. When G'd placed His palm before the eyes of Moses this was not to prevent him from having the intellectual/spiritual vision enjoyed by the nobles of Israel. The kind of intellectual/spiritual vision the nobles enjoyed as an exception was something Moses enjoyed on a year round basis. G'd merely wanted to prevent Moses's eyes from attaining a far greater vision, a revelation of a far more exalted vision of G'd. Whereas G'd has words which he employs to convey such concepts, I would not even attempt to record such ideas in print for fear some unworthy person will get to read them, someone who does not deserve the spiritual illumination such words provide.