Why does the Torah write "ve'es Mizbach ha'Olah Sam ... ", and not "Vayasem es Mizbach ha'Olah ... "?
When exactly, did Moshe perform the Avodah?
Rashi and Ramban: Moshe performed the regular Avodah, 1 even on the eighth day of the Milu'im, 2 after Aharon and his sons had been inaugurated, whereas they brought the Korbanos that were designated specifically for that day. 3
According to the Rashbam, this phrase is referring, not to the Milu'im at all, but to the future; it is informing us that on this Mizbe'ach, Aharon and his sons would bring the Olah and the Minchah permanently. This explanation is difficult to understand however, seeing as Aharon and his sons are not mentioned until Pasuk 31?
See Sifsei Chachamim.
Which Olah and Minchah is the Pasuk referring to?
Rashi: It is referring to the Olas Tamid and the Minchas Nesachim that accompanied it.