faith vs impure

faith is a noun but impure is not a noun.

Word	Noun	Adjective	Verb	Adverb
faith	Yes	No	No	No
impure	No	Yes	No	No

faith (noun)	impure (noun)
loyalty or allegiance to a cause or a person
a strong belief in a supernatural power or powers that control human destiny
complete confidence in a person or plan etc
an institution to express belief in a divine power

faith (adjective)	impure (adjective)
	(used of persons or behaviors) immoral or obscene
	combined with extraneous elements
	having a physical or moral blemish so as to make impure according to dietary or ceremonial laws