What is the meaning of "v'El Lev Shikutzeihem?"?
Rashi: Those whose hearts go to abominations ? those who remained in Yerushalayim and were not exiled. They err with idolatry.
Radak: Lev Shikutzeihem is as if their heart is divided into two, like Eliyahu told those who serve the Ba'al "Ad Masai Atem Posechim Al Shtei ha'Se'ifim" (Melachim I, 18:21). Their heart is =divided, and the desire follows the abominations more.
Malbim: This returns to verse 12 ? "you did not go in My Chukim." The verses interrupted with the death of Pelatyahu, the Navi screamed over it, and Hashem answered. Now it returns to say, you did not go in My Chukim; your heart clings to idolatry, Arayos and other abominations.
How did He put their ways on their heads?
Rashi: I will bring against them a sword and captivity; they will be exiled.
Radak: I will put payment on their heads.
Radak: I paid them according to their ways; they themselves are guilty.