I was acting on 'pure' intuition/instinct. [=only because of intuition/instinct and not for any other reason]
Don't expect me to believe you're '(as) pure as the driven snow'. [=morally perfect]
The relationship is over, 'pure and simple'. [=the relationship is completely over]
(..) You rescued me! You're amazing. You're-- You're wonderful. You're... a little unorthodox I'll admit. But thy deed is great, and thine heart is pure. - I am eternally in your debt. - And where would a brave knight be without his noble steed? I hope you heard that. She called me (..)2001 Shrek