Kural - 951

Save in the scions of a noble house, you never find
Instinctive sense of right and virtuous shame combined

Explanation
Consistency (of thought, word and deed) and fear (of sin) are conjointly natural only to the high-born.

Tamil Transliteration
Irpirandhaar Kanalladhu Illai Iyalpaakach
Cheppamum Naanum Orungu.