en_tn/jer/36/30.md

will ever sit on the throne of David

Sitting on the throne is a metonym for ruling as king. See how you translated "sits on the throne of David" in Jeremiah 29:16. Alternate translation: "will ever rule the Israelites as David did" (See: rc://en/ta/man/translate/figs-metonymy)

your corpse will be thrown out

This can be translated in active form. Alternate translation: "people will throw your dead body outside" (See: rc://en/ta/man/translate/figs-activepassive)

your corpse

"your dead body"

into the heat of day

"so that it is exposed to the dry heat of the daytime"

frost

ice that forms on grass during cold nights