What are "Sefayim"?
Rashi: They are streams.
Radak: Se'i and Sefayim 1 are high places - "he'Harim ha'Ramim v'Al Kol ha'Geva'os ha'Nisa'os" (Yeshayah 2:14). It was the way of idolaters [to put idolatry in high places - 2:20].
Radak citing Targum Yonasan: Nagrin 2 (pastures).
Seemingly, Se'i is a command "lift your eyes". Radak does not bring a source that Sefayim are high places! (PF)
Our text says Nagdin. Rashi (Yeshayah 49:9) says that these are streams.
Why is it written Shugalt, and we pronounce it "Shukavt"?
Rashi: Shugalt is an expression of Pilegesh (just the letters are re-arranged).
Radak: This is like in the Torah. It is written Yishgalenah (Devarim 28:34), and we pronounce it Yishkavenah - a cleaner expression.
Why does it say "Eifo Lo Shukavt"?
Malbim: He brings a proof that you were not to one husband. I will not say where you were Mezanah; the places are without number. Tell me, where were you not Mezanah?!
Why does it say "Al Derachim Yashavt Lahem"?
Rashi: You sat there to be ready to greet them.
Radak: You desired to serve idolatries of all the nations - "Mispar Arecha Hayu Elohecha" (2:28).
Malbim: You were not Mezanah covertly, rather, openly, on the road.
What is "ka'Aravi"?
Rashi: It is like one who dwells in tents. He is always found outside, in Midbaros. He is called Aravi, for he dwells in Aravah (plain).
Radak: The Aravim who dwell in the Midbar sit on the roads, hoping for passing caravans, to sell to them and buy from them.
Why does it say "va'Tachanifi Eretz"?
Malbim: You were not like a divorcee who clung to another man, rather, like one who flatters; his mouth and heart are not united. In your eyes you were like a Zonah under her husband, that when she lacks something, she requests from her husband, and is brazen to say 'you are Aluf Ne'urai' (refer to 3:4:4:1-2.
