2 Chronicles 13:5

5. A covenant of salt The meat-offering was a standing memorial of God’s covenant with man, and could never be lawfully offered without salt.

Leviticus 2:13. Salt, the symbol of perpetuity and incorruptibility, became therefore proverbially associated with the Israelitish notion of a sacred and inviolable covenant. Hence “a covenant of salt” is equivalent to “a holy and inviolable covenant.” Compare Numbers 18:19.