Why does it say "Chiko Mamsakim"?
Rashi according to the metaphor: His words are pleasant, e.g. "v'Seret la'Nefesh Lo Sitenu bi'Vsarchem... Ani Hashem" (Vayikra 19:28) - I am faithful to pay reward. Is there a sweeter palate than this? Do not do destructive deeds, and you will receive reward! "Uv'Shuv Rasha me'Rish'aso Asher Asah v'Asah Mishpat u'Tzedakah Aleihem Hu Yichyeh" (Yechezkel 33:19) - His sins are considered merits 1 . Is there a sweeter palate than this?!
Seforno: "Mah Hashem Elokecha Sho'el mi'Imach Ki Im Leyir'ah... l'Tov Lach" (Devarim 10:12).
Malbim (Melitzah): The palate represents tasting Chachmah and sensing it - "Ki Ozen Milin Tivchan v'Cheh Yit'am Le'echol" (Iyov 34:3). I.e. the Chachmah that is revealed from Him is sweet.
Yuma 86b: This is if he repents due to love.
Why does she add "Chulo Machamadim"?
Seforno: The entire intent is that we attain eternal life, which is Nechemadim more than anything else.
Malbim (Melitzah): This refers to desire. All desire Him, for He wants only good and Chesed.
Why does she say "Zeh Dodi"?
Rashi: This is the appearance of my Beloved and my Companion. I am lovesick for Him!
Malbim (Melitzah): These are His descriptions via which He is recognized. He is not recognized via Himself, only via His actions. I love Him so strongly because I recognize His attributes, Tov, Chachmah and perfection.
Why does she add "v'Zeh Re'i"?
Malbim (Melitzah): Also I am a spiritual entity Ne'etzal (copied) from Him, and I have a partial semblance of perfection like Him, like a part that resembles the whole. David said five times "Barchi Nafshi" corresponding to Hashem and the Neshamah. Just like Hashem fills the world, and sustains the world, and sees and is not seen... similarly the Neshamah... (Brachos 10a).
