covenant

(noun) a signed written agreement between two or more parties (nations) to perform some action. Synonyms: compact, concordat.

(noun) (Bible) an agreement between God and his people in which God makes certain promises and requires certain behavior from them in return.

(verb) enter into a covenant.

(verb) enter into a covenant or formal agreement. Examples: "They covenanted with judas for 30 pieces of silver." "The nations covenanted to fight terrorism around the world."