behest vs bidding

behest and bidding both are nouns.

Word	Noun	Adjective	Verb	Adverb
behest	Yes	No	No	No
bidding	Yes	No	No	No

As nouns, bidding is a hypernym of behest; that is, bidding is a word with a broader meaning than behest:

Other hypernyms of behest include bid, command, dictation.

behest (noun)	bidding (noun)
an authoritative command or request	a request to be present
	(bridge) the number of tricks a bridge player is willing to contract to make
	an authoritative direction or instruction to do something