Prove the following statement, then write down its converse. “For all x ∈ Z, if x ≡ −1 (mod 7) then x^3 ≡ −1 (mod 7)."

Would this statement be false? I'm kinda confused on how to solve this question. I can only figure out that x ≡ -1 (mod 7) when x=6 and hence x^3 ≡ −1 (mod 7) is also true.