1)
Is this connected to the previous Nevu'ah?
1.
Malbim: Yes. It explains why after seven months they will not find flesh of the dead, for Chayos and birds will eat the flesh.
2)
Why does it say "Hikavtzu" and "He'asfu"?
1.
Malbim: "Hikavtzu" is scattered individuals gathering together. After they are gathered, "He'asfu" is to come together to the place of the killed. Radak (18) ? He calls them to eat between the killing and burial.
3)
Why is it called "Zevach Gadol"?
