Why does it say that now, fear of Hashem should be on you?
Malbim: Now I taught that He is the judge and litigant.
Why does it say "Shimru va'Asu"?
Malbim #1: "Shimru" is for Lavim, e.g. "Lo Sikach Shochad", "Lo Sakir Panim." "Va'Asu" - Mitzvos Ase, like "b'Tzedek Tishpot."
Malbim #2: Favoritism usually causes inaction, not to judge a powerful person - therefore, it says Asu. A bribe causes tilting judgment - therefore it says Shimru.
Why does it say "Ein Im Hashem Elokeinu Avlah u'Masa Fanim u'Mikach Shochad"?
Rashi: Since He is with you in Mishpat, He does not want you to do injustice in Mishpat.
Malbim: Tilting Mishpat is via injustice, or favoring a litigant, or taking a bribe to help a litigant. These do not apply, for Hashem is a litigant and judge.
