1)
Why does it say "la'Mizbe'ach vela'Bayis"?
1.
Malbim: Some guarded the Mizbe'ach, i.e. those guarding inside, from the entering Mishmar. Some guarded the Bayis, i.e. those guarding outside, from the leaving Mishmar. Both of them stood from the right end to the left end, guarding inside guarding.
