જાતે કાફર, ને હાડે કાફર.

jātē kāphara, nē hāḍē kāphara.

Literally: An infidel by caste, and an infidel to the bone.
What it means: Said of someone who is thoroughly wicked, untrustworthy, or unyielding in their bad nature.

Also said as

ગુજરાતી કહેવતસંગ્રહ (Gujarati Kahevat Sangrah) (1923) · read from the scan by machine — the Gujarati itself is unchecked · English is machine-made and nobody has checked it yet

Heard it differently, or know we've got the sense wrong? Tell us — that is exactly the kind of correction this needs.