What is the meaning of "Rigzu v'Al Techeta'u"?
Brachos 5a: A person should always arouse his Yetzer Tov to fight his Yetzer ha'Ra -- "Rigzu v'Al Techeta'u." If he does not overpower his Yetzer ha'Ra, he should learn Torah -- "Imru bi'Levavchem." If he still does not overpower it, he should recite Shema -- "Al Mishkavchem." If he still does not overpower it, he should think about the day of death -- "v'Domu Sela."
Rashi: Be fearful in front of Hashem and do not sin. Radak - this is like "v'Ragzu v'Chalu" (Devarim 2:25). If you will not fear me, fear Hashem! Do not sin to chase me and rebel against me!
Sha'arei Teshuvah 1:4: Be excited and pained over what you sinned, and do not sin more! It does not say 'fear', rather, "Rigzu", which implies pain over the past and the present, like "Al Tirgazu ba'Darech" (Bereishis 45:24), "v'Sachtai Ergaz" (Chabakuk 3:16).
Malbim: Do not sin, to slander David.
Erech Apayim (2:8, citing Sefer ha'Midos): Sometimes one must be angry to avoid bad thoughts - i.e. he is angry at himself 1 .
Erech Apayim: This is the only Heter for anger, and it should be used only when there is no alternative.
What do we learn from "Imru bi'Levavchem"?
Refer to 4:5:1:1.
Brachos 5a: Even if one already said Keri'as Shma at night in Beis ha'Keneses, he should repeat it before sleeping. Shma, which mentions "Al Levavecha," should be "Al Mishkavtem (said upon going to sleep) v'Domu Sela."
Rashi: Put to your hearts that Hashem commanded about this.
Radak: Thoughts in the heart are called Amirah - "ha'Omrah bi'Lvavah" (Yeshayah 47:8).
Radak citing Moreh ha'Nevuchim (1:50, 59): Esteemed intellectuals should recognize the truth and praise of Hashem in their hearts, lest they say improper words 1 .
Radak: The Mizmor does not discuss this!
Why does it say "Al Mishkavchem"?
Radak: When a person lies down, his mind is free from worldly affairs, and his thoughts are clear.
Malbim: Instead of discussing David's sin with Bas Sheva, ponder your sins of [intimacy] through lying!
Why does it say "v'Domu Sela"?
Radak #1: Cease to rebel against me. Demamah is silence from speech and noise - "v'Yidemu Lemo Atzasi", "Demamah v'Kol Eshma" (Iyov 29:21, 4:16).
Radak #2: Sometimes Demamah is ceasing to act or move - "Yakem Se'arah li'Dmamah" (elsewhere, 107:29), "Me'ai Rutechu v'Lo Damu" (Iyov 30:27), "l'Even Dumam (Chabakuk 2:19) and similar verses. Here it means 'cease your deeds.'
Radak: Refer to 4:5:2:5 and the note there.
Malbim: Cease to slander David.
