Here "heart" represents a person's inner being. Feeling sorry is spoken of as if the heart were tender. Alternate translation: "because you felt sorry" or "because you repented" (See: [[rc://en/ta/man/translate/figs-metonymy]] and [[rc://en/ta/man/translate/figs-metaphor]])
The abstract nouns "desolation" and "curse" can be stated as an adjective and a verb. Alternate translation: "that I would make the land desolate and would curse them" (See: [[rc://en/ta/man/translate/figs-abstractnouns]])
Yahweh speaks of himself by name to express the certainty of what he is declaring. See how you translated this in [2 Kings 19:33](../19/33.md). Alternate translation: "this is what Yahweh has declared" or "this is what I, Yahweh, have declared" (See: [[rc://en/ta/man/translate/figs-123person]])