Who said "Hikshavti"?
Radak: Yirmeyah said so. When I go among them, I listen to them, if they speak properly or not.
Radak citing Targum Yonasan: Hashem said so. I hearkened, and it is revealed in front of Me.
Malbim: Hashem said, I listened to your answer.
What is "Lo Chen"?
Rashi: It is not [Radak - good and] proper. Ken is like "Ken Benos Tzlafchad" (Bamidbar 27:6).
Malbim: I understand that your confession at the time of Teshuvah is not proper.
Why does it say "Ein Ish Nicham"?
Malbim: When punishments come, they repent, but they do not regret their bad deeds themselves. They regret and mourn only the damage that came to them via their deeds. This is like a thief who is caught, and he does not regret stealing, only being found.
Why does it say "Kulo Shav bi'Merutzasam"?
Rashi: They return to their first course - they sin and return to sin.
Why is it written b'Martzusam, and we pronounce it bi'Merutzasam?
Radak: The Kesiv is plural, of the Klal (their Meretz, i.e. vigor). The pronunciation refers to individuals - they run to return like a horse racing in war.
Why does it say "k'Sus Shotef ba'Milchamah"?
Radak: It is like a river that is Shotef (raging and overflowing) in its haste.
Mesilas Yesharim (Perek 2): They pursued and went in their habits and ways without taking time to be meticulous about heir deeds and ways. It turns out that they fall in evil without seeing it.
Malbim: When a horse encounters the enemy in war and runs back, its primary purpose of running back is so it can return to pounce on the enemy with more energy. So their Teshuvah from sins is not in order to cease them, rather, to return to do them again even more, when they have relief from their affliction.
