1)
Why did he build the Mikdash in Har ha'Moriyah?
1.
'Rashi': It is because Hashem appeared to David there, in Aravna's granary, when the plague stopped.
2.
Malbim: "B'Har Hashem Yera'eh" (Bereishis 22:14) hints that in the future, Hashem will reveal His Shechinah in the place of Akeidas Yitzchak.
2)
How did Hashem appear to David there?
1.
Malbim: Fire descended from Shamayim.
3)
What is the meaning of "Asher Hechin bi'Mkom David"?
1.
Malbim: David dug the foundations there, like Chazal said (Sukah 53b); the place became called Mekom David.
