Why does it say that Hashem's Amaros (what He says) are "Amaros"?
Rashi: He is able to fulfill them. People's Amaros are not Amaros, for they die, and they cannot [always] fulfill them.
Why does it say that Hashem's Amaros are "Tehoros"?
Rashi: They are clear and fulfilled. Everything that He promises, He does. He promised to me salvation and kingship!
Radak: There is no dross; all are true.
Malbim: This is in contrast to those who oppose Emunah and strive to falsify Torah and expound improperly. The sayings, metaphors and stories in the Torah, which are garments and bodies to Divine Chachmah and secrets hidden in [the Torah], which are like the Neshamah, are Tehoros. Also the stories and metaphors are clean from any dross - unlike philosophers' sayings, who clothe Chachmah in fictional tales without any benefit. The Torah is different; also its revealed part is a garment for the hidden. It is Tahor, and full of Chachmah and Musar. The interior under the garments is exceedingly refined, dear silver.
Why are they called "Kesef Tzaruf"?
Rashi: They are like refined silver, revealed to the entire land.
What is the meaning of "ba'Alil"?
Rashi #1 (from Rosh Hashanah 21b): This is an expression of exposure - 'whether or not [the new moon] was seen ba'Alil'.
Rashi #2: Some say that it is an expression of Ma'aleh (an attribute). The silver is refined in the best earth. One makes a smelter's oven from choice earth.
Rashi #3: It is like Ali - "b'Soch ha'Rifos ba'Ali" Mishlei 27:22], a Kli in which people crush. Alil is a furnace in which they melt gold and silver 1 .
Rashi #4, Targum Yonasan: "Ba'Alil la'Aretz" is like Ba'al Yad, Master of the land. Hashem refined [His words]. Radak - the last letter of the root (Lamed) is doubled, like Sagrir. The prefix Lamed in la'Aretz is extra, like "Hargu l'Avner" (Shmuel II, 3:30), "ha'Shelishi l'Avshalom" (Divrei ha'Yamim I, 3:2). Or, it is in place of the prefix Hei ha'Yedi'ah (to identify).
Rashi: This is wrong. Ali is not the mortar in which the matter is crushed, rather, the pestle used to crush it!
What is "Shiv'asayim"?
Rashi (Rosh Hashanah 21b): It is seven times seven. The Gemara says that 50 gates of understanding were created, and 49 were given to Moshe 1 - "va'Techaserehu Me'at me'Elokim" (8:6. Refer to 8:6:1:1.)
Radak: It is many times, repeated. Often seven refers to many times - "Sheva k'Chatoseichem" (Vayikra 26:21), "Sheva Yipol Tzadik v'Kam" (Mishlei 24:16), "Shiv'ah Einayim" (Zecharyah 3:9). Also "Shiv'asayim Yukam" (Bereishis 4:15) is many times, repeated.
Yerushalmi Sanhedrin 2:2, Yalkut Shimoni (Tehilim 658): For every matter, Hashem showed Moshe 49 reasons for Tum'ah, and 49 for Taharah. (Maseches Soferim 16:5 expounds this from "v'Diglo Alai Ahavah" (Shir ha'Shirim 2:4).)
