covenant of salt
A long-lasting agreement.
... God gave the Kingdom unto David for ever, or by a Covenant of Salt.
noun
An agreement to do or not do a particular thing.
A promise, incidental to a deed or contract, either express or implied.
A pact or binding agreement between two or more parties.
An incidental clause in an agreement.
verb
To enter into, or promise something by, a covenant.
Jupiter Covenanted with him, that it should be Hot or Cold, Wet or Dry, […] as the Tenant should Direct.
and they covenanted with him for thirty pieces of silver
To enter a formal agreement.
To bind oneself in contract.
To make a stipulation.