1)
What is "Tzilecha"?
1.
Malbim: Not only He is Shomerecha from mishaps of the land. He is also shade from natural evils of Shamayim 1 .
2.
Lev Eliyahu (Shemos p.62): When you see a shadow, you know that something makes the shadow. The entire creation is the shadow of Hashem, hidden miracles, like the Ramban said.
1
Perhaps this refers to eclipses (PF). A lunar eclipse is a bad Siman for Yisrael. A solar eclipse is a bad Siman for the entire world, or Yisrael, or the other nations (Sukah 29a).
2)
What is the meaning of "Al Yad Yeminecha"?
1.
Radak: He helps you in all your deeds.
2.
Malbim: Unlike other Shomerim, He is constantly at your side, like your shadow.
