Here the word "heart" represents the thoughts and intentions. Hezekiah speaks of deciding to do something as if that thing were in his heart. Alternate translation: "it is my intention" or "I have decided" (See: [[rc://en/ta/man/translate/figs-metonymy]] and [[rc://en/ta/man/translate/figs-metaphor]])
Hezekiah speaks of Yahweh no longer being angry with them as if Yahweh's anger were a person who turns away from them Alternate translation: "he may no longer be angry with us" (See: [[rc://en/ta/man/translate/figs-metaphor]] and [[rc://en/ta/man/translate/figs-personification]])