Seeing as Moshe is being addressed, why did Hashem (or the angel) say "ve'Nigash Moshe", and not "ve'Nigashta"?
Ramban #1 (citing Ibn Ezra): Here too, it is common practice for the Torah to state the name in place of the pronoun. 1
Ramban #2: In fact, the current instructions were said to Aharon as well. Consequently, in this Pasuk, it was necessary to mention Moshe specifically, to preclude Aharon. 2
Why were the elders denied the privelege of ascending Har Sinai?
Rashi: Refer to 5:1:1:1*.