When did this Pasuk take place?
Rashi (in Shemini), 1 Ramban (in Pasuk 2): It took place on the eighth day of the Milu'im, when the Shechinah came to rest in the Mishkan.
Rashbam (in Pasuk 35): To demonstrate Hashem's love of Yisrael, no sooner had Moshe finished setting up the Mishkan than the Shechinah rested in it, 2 and Moshe was unable to enter. 3
Seforno: As soon as Moshe had finished setting up the Mishkan and performing the Avodah in it.
See Rashi in Vayikra 9:23 (Ramban).
Both the Rashbam and the Seforno - see answer #3 - are referring to the eighth day, like Rashi and the Ramban. Refer to 40:34:1:1*.
Why did the cloud cover the Ohel Mo'ed?
Oznayim la'Torah: To prevent the people from looking at the Shechinh which was about to enter the Mishkan. 1
Oznayim la'Torah: In keeping with the Pasuk in Acharei-Mos Vayikra, 16:2 "Ki be'Anan Era'eh al ha'Kapores".
What does the Torah mean when it says "u'Chevod Hashem Malei es hs'Mishkan"?
Hadar Zekenim: Really, Hashem contracted His Glory, and the Mishkan filled it, only it is more rspectful to say that His Glory filled the Mishkan, since it implies that Hashem's Glory is larger than the Mishkan and the Mishkan filled it.
Seforno: It means that the Glory of Hashem was revealed in the entire Mishkan abut not one inch outside it.
