attest vs declare

attest and declare both are verbs.

Word	Noun	Adjective	Verb	Adverb
attest	No	No	Yes	No
declare	No	No	Yes	No

As verbs, declare is a hypernym of attest; that is, declare is a word with a broader meaning than attest:

attest (verb)	declare (verb)
authenticate, affirm to be true, genuine, or correct, as in an official capacity	state emphatically and authoritatively
provide evidence for; stand as proof of; show by one's behavior, attitude, or external attributes	state firmly
give testimony in a court of law	make a declaration (of dutiable goods) to a customs official
establish or verify the usage of	declare to be
	announce publicly or officially
	proclaim one's support, sympathy, or opinion for or against
	designate (a trump suit or no-trump) with the final bid of a hand
	authorize payments of