Skanda Purana 17.18.226

17.18.226

anyāyenārjitaṃ vittaṃ na deyaṃ śreya icchatā ..
vyarthamabrāhmaṇe dānamārūḍhapatite tathā ..226..

Wealth acquired unjustly should not be given by one desiring welfare. / A gift to a non-brahmin is futile, and likewise to an apostate ascetic;