Rashi: [You ceased] his shining. The Targum of "b'Tzaharayim" (Devarim 28:29) is b'Tihara. This is like "uch'Etzem ha'Shamayim la'Tohar" (Shemos 24:10).

Ibn Ezra: You ceased his Mikdash, which is Tahor. The Mikdash is attributed to David, for he prepared the gold and silver for it.

Radak: You ceased his clarity and the glory of his kingship. Mit'har is a noun (clarity), like "uch'Etzem ha'Shamayim la'Tohar" (Shemos 24:10).

Malbim: The first time that [Nebuchadnetzar] conquered the kings of Yehudah, [Tzidkiyah] did not have strength and sharpness, but at least he had purity and cleanliness, and not filth. However, after [Tzidkiyah] was submissive to him, and swore to serve him, and returned to fight him, and transgressed the Shevu'ah that Nebuchadnetzar imposed on him, the Tohar of his sword blade ceased ¹ . He was considered like one who annuls a Shevu'ah and Bris.

Rashi: You lowered and destroyed. Every expression of Shechiyah (bending), Yonason translates Mager.

Radak: You made it fall. The Targum of "va'Yipol Rochvo Achor" (Bereishis 49:17) is va'Ymager Rochveihon la'Acharonan.

Malbim: You cast his throne to the ground, and Malchus Yisrael totally ceased.