Why did Moshe choose specifically the Ketores with which to make the test?
Rashi: Because 'The nations of the world', he told them, 'have many religions and many priests, who all 1 gather in one house. We have only one G-d, one Aron, one Torah one Mizbe'ach and one Kohen Gadol - and you, two hundred and fifty men all want the Kehunah Gedolah! I want it too! So here's the most precious service of all - the Ketores 2 , which is more treasured than all the Korbanos, and which contains poison 3 - the poison that killed Nadav and Avihu'. This was Moshe's warning to desist from going ahead with the test. He hoped that that they would do Teshuvah and relent. 4
Ramban #1 (in Pasuk 5) #1: It was his own idea.
Ramban #2 (in Pasuk 5, citing the Ibn Ezra): Refer to 16:4:1:2.
Ramban (in Pasuk 5) #2: It came through Ru'ach ha'Kodesh 5 .
Others have the text 'who do not all gather ... '.
Moshav Zekenim (in Vayikra 12:8, citing a Midrash): Ketores is the most precious Korban, dearest, since it is not brought to atone for a sin. Olah is for sinful thoughts, Shelamim is for (Bitul) Mitzvas Asei ? Ketores is only for Simchah, as the Pasuk writes in Mishlei 27:9 "Shemen u'Ketores Yismach Leiv".
Others have the text "ve'Sam ha'Maves Nasan lahem be'Socho'.
Ramban: Either Moshe issued Aharon with a temporary ruling permitting him to bring voluntary Ketores, or he brought the morning Ketores.
Ramban: As did his command to Aharon later in the Parshah (See 17:11). He received Ru'ach ha'Kodesh whenever necessary; the Torah writes about him "b'Chol Beisi Ne'eman Hu".
What are the implications of "Vehayah ha'Ish asher Yivchar bo Hu ha'Kadosh", which otherwise seems obvious?
Rashi and Seforno: He was warning them that the chosen person was already Kadosh, that he was the one who would come out alive and all the others would die! 1
And he stressed this in the hope that they would do Teshuvah, since 'Hashem does not want the Rasha to die' - Yechezkel, 18:32.
