There is a famous dispute between Rashi and the Ramban about when the laws of the משכן described in this week's parsha were actually given. According to the opinion of Rashi, namely that the laws of the משכן were only introduced after חטא העגל, what did the Torah mean in שמות כג:יט when it gave the mitzvah of ביכורים which involves bringing one's first fruits to the בית המקדש? If the idea of building God a house only began after חטא העגל, how could the Torah already be giving commandments relating to this house before חטא העגל?
Both in the ten commandments (שמות כ:ד) and immediately following them (שמות כ:כ), we are warned against making any idols, statues, or gods of gold and silver. Rashi (כ:כ) interprets the latter pasuk as being an explicit prohibition against making the gold כרובים (cherubs) out of silver and against making extra כרובים. If the existence of כרובים raises such serious problems of idolatry, why does the Torah command us to place two כרובים on top of the ארון? Why are these two not a problem of עבודה זרה?
When speaking about the materials listed in the Mishkan, the Torah repeatedly mentions זהב טהור. This is the only time in the Torah that gold is mentioned as being specifically "pure." Could this be related to theזהב טוב mentioned only in פרשת בראשית?