1)
Why did they not recognize him?
1.
Rashi: His face changed due to the afflictions.
2)
Did they throw earth to Shamayim?!
1.
Rashi: They threw it above their heads. This was a custom of mourning.
2.
Devar Eliyahu: They threw it high. "Ha'Shamaimah" is an exaggeration, like "Arim Gedolos u'Vetzuros ba'Shamayim."
