What are the ramifications of "Zeh ha'Davar ... "? What is it referring to?
Rashi (on Pasuk 23): When, after the seven days that Moshe brought served in the Mishkan, the Shechinah did not appear, the people were ashamed, and asked him whether all their efforts to atone for the sin of the Golden Calf had been in vain, he replied that what Hashem commanded that, for the Shechinah to appear, Aharon his brother, who was more worthy than him, should perform the Avodah.
Ramban #1 (citing Ibn Ezra): It belongs after Pasuk 1, and informs us that Moshe called Aharon and his sons and the elders and said to them "Zeh ha'Davar asher Amar Hashem ... . Vayomer el Aharon ... ". 1
Ramban #2: After Moshe presented them with the list of all the Korbanos, they brought them to the Ohel Mo'ed, and that is when he warned them that if they bring the Korbanos exactly according to his instructions, the Shechinah would appear to them.
Seforno: Moshe told them. 2
Targum Yonasan: 'This is what you shall do: Remove the Yeitzer ha'Ra from your hearts and the Shechinah will appear to you!'