What is the meaning of "Achos Lanu Ketanah"?
Refer to 8:8:2:1.
Rashi: We have among the lower beings, one that is Mis'acheh (sewn), connected and desires to be with Us. She is small, and makes (considers) herself smaller than all nations - "Hashem did not choose you because you are great" (Devarim 7:7). Rather, they belittle themselves. Achos is an expression of sewing - 'these tears may not be sewn back [normally]' (Mo'ed Katan 26a).
Seforno: Hashem answers, you are pained over the delay of Shechinah among you and Mashi'ach's coming. Even when the exiles are gathered, the congregation of Tzadikim will be small!
Malbim (Melitzah): This begins Shir ha'Alef 1 . The Nefesh speaks in front of Kel on behalf of its young sister - the formless Ru'ach, lest the king take it (it join with the body) and perish with the body. Researchers call this Ru'ach 'acquired intellect'; its nature is not to be eternal. It is a power dependent on physicality, and it perishes with [the body]. However, via proper deeds, Torah and Avodah, it can be purified to become eternal. Kabalists say that the Ru'ach remains in the lower Gan Eden, and the Divine Neshamah that goes above [to the higher Gan Eden] is also clothed with the Ru'ach when it descends.
Malbim (Mashal): Refer to 8:8:3:4.
Malbim learns from "va'Yhi Shiro Chamishah va'Alef" (Melachim I, 5:12) that Shir ha'Shirim is five Shiros, and also Shir ha'Alef. It is called so based on "Ish Yavi b'Firyo Elef Kasef; ... ha'Elef Lecha Shlomo" (11-12).
What is the meaning of "[Achos Lanu Ketanah] v'Shadayim Ein Lah"?
Torah Temimah citing Pesachim 87a: This refers to Eilam (the province in which is Shushan). It merited to learn Torah, but not to teach. (Daniel and Mordechai were there, but they did not spread Torah.)
Rashi: It says about Galus Egypt "Shadayim Nachonu" (Yechezkel 16:7) when the time for Ge'ulah came. Now, Shadayim Ein Lah - the time of love did not come.
Seforno: The few [Tzadikim] do not teach Da'as to the nation, and they do not protest to make them cease sinning when the commoners engage only in temporary life - "Oseh Mikneh v'Kinyan" (Yechezkel 35:12).
Malbim (Melitzah): The Ru'ach does not influence, for it is acquired intellect, and not Ne'etzal from Hashem. It only receives.
Malbim (Mashal): Refer to 8:8:3:4.
Why does it say "Mah Na'aseh la'Achoseinu ba'Yom she'Yedubar Bah"?
Rashi: When the nations whisper about [Yisrael] to eradicate her - "Lechu v'Nachchidem mi'Goy" (Tehilim 83:5).
Seforno: I and My Mashi'ach - also he will be like a fire that refines silver.
Malbim (Melitzah): What will happen when it is taken to Beis ha'Melech (Shlomo, the body, to perish with it in the grave)? How will it be saved to live forever?
Malbim (Mashal): She speaks to her beloved on behalf of her young sister - what will be if ha'Melech Shlomo wants to take her?
