Ki Tisa - The Burning of the Golden Calf

A poster on Avodah asked the following question:

The Pasuk (Shemos 32:20) recounts that Moshe burned, then ground the Eigel. Ibn Ezra explains that 'burned' doesn't mean 'melted' as one might have thought given that the Eigel was Zahav), but that there is a substance that when inserted into a fire with gold makes it irreversibly black. Does anyone know what this substance is?

IANAMetallurgist, but it sounds like it could be sulfur (or some natural compound containing such). Although gold is inert to the majority of chemical attacks, most gold jewelry contains a significant fraction of other metals such as silver and copper, as pure gold is too soft and malleable to be very useful. These alloys were also known in the ancient world. Metal sulfides have inferior mechanical properties compared to the metals themselves, so that once the surface of a piece of metal is sulfidized, it would crack and flake off, especially at high temperatures (and if agitation is used), revealing a new clean layer of metal to be attacked, until eventually one would get a blackish powder. I'm not sure how long this "eventually" would take, but if the metal was concurrently mechanically ground to maximize its surface area (as per "vayitchan ad asher dak"), the rate of the reaction would be accelerated.

I would not have thought that this process could cause a color change in gold of a relatively high purity, but I found a report by the World Gold Council which reported a phenomenon of the blackening of gold in the Middle East and India at purities considerably higher (up to 22K) than that which tarnishes elsewhere in the world, and suggested that the cause may be significant exposure to foods and spices that are high in sulfur compounds. At high temperatures and using large amounts of the sulfidizing reagent (i.e., an amount of mass equal to that of a significant fraction of the non-gold components), the
reaction may well proceed at a much faster rate.

Shelach 1

1) Many people are familiar with Rashi's comment on 13:23 (based on the Pesikta) that Yehoshua and Kaleiv did not join with the other spies in carrying back from the fruit of the land, since they knew that their intent was to use the fruit as props to slander the land. Less well-known is the opposing comment of the Midrash Rabbah (16:10), which says that the spies had no intent in taking back any of the fruit of the land, were it not for Kaleiv drawing his sword and saying, "If you don't take from the fruit of the land, either you'll have to kill me or I'll kill you". I think that this is a wonderful example of the concept of opposing midrashim (reconciliation is perhaps possible, but seems to be very dachuk). It's interesting that Kaleiv added in the option of them killing him, rather than the more familiar reverse ("Do this or I kill you"). Recall, the spies weren't entirely evil people (after all, they were chosen for a reason), so Kaleiv putting his life down on the line was probably a safe manuever, maybe intended to shock them out of following through on their evil plan. Alternatively, perhaps he mentioned it because he was vastly outnumbered, and, if violence broke out, he would most likely be the victim.

2) In P' Ki Tisa (34:6), following the sin of the Golden Calf, HaShem teaches Moshe the 13 middos that can be used to invoke His mercy. In this week's parsha (14:18), Moshe uses only 6 of them. He uses one of the two sh'mos HaVaYa, Erech Apayim, Rav Chesed, Nosei Avon, (Nosei) Pesha, and Nakeih, but omits the other sheim HaVaYa, Keil, Rachum, and Chanun, (Rav) Emes, Notzeir Chesed LaAlafim, and (Nosei) Chata'ah. (This is based on the opinion of Rabbeinu Tam on R"H 17b, as quoted by Artscroll in their siddur's commentary on Seilchos, but in their commentary in the siddur on Tashlich, they say that Moshe uses 9, which is equal to the number of words mentioned thus far). He also mentions "Lo Y'nakeih", which seems to be a midah of pur'anus (unless one wants to include such non-cleansing as being a part of HaShem's mercy), and "Pokeid Avon Avos al Banim". I'm sure this discrepancy is dealt with in many places.
The Oznayim L'Torah, for one, explains the absence of 4 of the first 6 terms by saying that this time was not fit for a request for mercy for those who did not sin, since everyone had sinned and had not yet repented, but rather focused on a request for a stalling of the execution of HaShem's anger. Similarly, he left out "Chata'ah", since that refers to unintentional sins, while here the sin was intentional (although it would seem that the same could be said by the Calf). I don't see that he explains the other two missing terms, but following in the same vein, since the nation really was deserving of extermination, emes was undesirable in this scenario. As for notzeir chesed la-alafim, which would seem to be a reference to z'chus avos, perhaps by rejecting the land, they had cut themselves off from z'chus avos - not sure how to expand on this.

Ki Tisa 2

I was browsing through my new copy of Sichos Mussar by R' Chaim Shmulevitz earlier this week, and saw that he has a piece on the Cheit Ha-Eigel. He asks what is probably one of the most popular questions on a parsha in Chumash - namely, what's up with the calf? How can people who just 6 weeks ago heard HaShem speak to them suddenly turn and build an idol? There are many answers given to this question, such as that it was only meant as an replacement for Moshe and that it was only 3000 bad eggs who were looking for an excuse to worship avodah zarah. R' Shmulevitz has an interesting take on the matter.

He quotes the gemara in Chagiga in which Rebbi, when reading from Megillas Kinos, accidentally drops it, and exclaims, "From a great height to a deep pit!" R' Shmulevitz explains the significance of this statement by contrasting a book with a person. A book, when it falls, can be damaged by the impact. However, it does not inherently suffer from its displacement from a high place to a low place. A human being, on the other hand, not only can be injured from the impact, but also simply from the change in location. It was this dual injury that led Bnei Yisroel to sin with the eigel. When the Satan misled them into thinking that Moshe died in heaven, it had a cataclysmic effect on them, that led them into a downwards tailspin that they were unable to break out of until they hit rock bottom, worshipping avodah zara.

R' Chaim contrasts this to the downfall of Shlomo. He quotes a midrash whose location (Koheles Rabbah?), context, and exact wording escape me, but it goes something like "Shlomo started out ruling over the entire world, then part of the world, then over Eretz Yisroel, and finally he only ruled over his staff." R' Shmulevitz notes the significance of this last clause. Even when Shlomo had frightening downfall, he refused to let himself hit rock bottom, but rather maintained his mida of malchus at the very least over his own staff. This alone could be seen as a very minor distinction from ruling over nothing at all, but to the contrary, it was this small elevation from rock bottom, this small measure of maintaining self-control, that enabled him to ultimately return to his full powers. Had the Jews been able to stop their downfall at any point, they never would have fallen to such a depth. However, as they kept falling further and further down, there was nothing to stop them from reaching this low level.

Ki Tisa 1

Pop quiz - Where are cinnamon and myrrh mentioned in this week's parsha?