1)
How will they resemble earth?
1.
Malbim (Tehilim 18:43): Finely ground earth scatters in every direction - and so the enemy soldiers will flee in every direction
2)
What is the meaning of "Adikem"?
1.
Radak: This is like "va'Yidak l'Afar" (Melachim II, 23:6).
3)
What is the meaning of "Erka'em"?
1.
Rashi: I will trample them. This appears many times in Sefer Yechezkel, e.g. "u'Rka b'Raglecha", "v'Rak'acha b'Ragel" (6:11, 25:6). Malbim (Tehilim 18:43) - this refers to those who remained in their cities.
2.
Radak: This is [flattening,] like "va'Yrak'u Es Pachei ha'Zahav" (Shemos 39:3).
