1)
Why does it say "Mi Ya'aleh b'Har Hashem"?
1.
Rashi: Even though all dwellers of the world are His, not all are proper to come close to Him - only "Neki Chapayim
2)
What is "Mekom Kadsho"?
1.
Radak (1): It is Har ha'Moriyah, which is opposite (below) Kisei ha'Kavod.
3)
Why does it say "u'Mi Yakum bi'Mkom Kadsho"?
1.
Malbim: It is an attribute to ascend Har Hashem. A higher level is to stand there and cling to Him, and go in front of Him in Kodesh.
