“A covenant of salt”
Do you not know that the LORD, the God of Israel, has given the kingship of Israel to David and his descendants forever by a covenant of salt? (2 Chronicles 13:5 BSB)
What it sounds like today
A strange, almost throwaway reference to salt.
The cultural key
'A covenant of salt' is an ancient idiom for a binding, permanent agreement. Salt preserves food from decay and does not itself spoil, so it became the natural emblem of a pact meant to last forever; to share salt, or to seal a deal with it, was to make the bond unbreakable. Every grain offering had to be salted with 'the salt of the covenant' (Leviticus 2:13), and the priests' portion is called 'an everlasting covenant of salt' (Numbers 18:19). Here King Abijah invokes the phrase to argue that God's grant of the throne to David's line is permanent and cannot be overturned by the northern rebellion. A modern reader hears an odd mention of seasoning; the first hearers heard a guarantee of permanence.
Recovered meaning
'A covenant of salt' is idiom for a permanent, unbreakable pact, sealed by salt because salt preserves and never spoils. Abijah uses it to claim the throne of David is granted to his house forever.