1)
Why were there nails?
1.
'Rashi': They were to firmly fasten the gold to the wood.
2.
Malbim: He could not plate gold on the stone floor. Rather, he put thick gold sheets, and nailed them to the floor.
2)
What is the meaning of "li'Shkalim"?
1.
'Rashi': In the weight of Shekalim, it was that of 50 gold Shekalim. Malbim ? each nail was 50.
3)
What are the Aliyos?
1.
Malbim #1: They are the Aliyos over the Kodesh ha'Kodoshim.
2.
Malbim #2: They are all the Aliyos.


