en_tn/jer/04/18.md

your conduct and your deeds have done these things to you

Here "conduct" and "deeds" are spoken of as if they are people that could do things. These abstract nouns can be expressed with the phrase "what you have done." Alternate translation: "These things are happening to you because of what you have done" (See: rc://en/ta/man/jit/figs-personification and rc://en/ta/man/jit/figs-abstractnouns)

It will strike your very heart

Here "heart" probably refers to the emotions, and "strike your very heart" probably refers to causing them to suffer terribly. Alternate translation: "It will be as if it strikes your very heart" or "It will cause you to suffer terrible anguish" (See: rc://en/ta/man/jit/figs-metaphor)