Manusmriti
न स्वामिना निसृष्टोऽपि शूद्रो दास्याद् विमुच्यते । निसर्गजं हि तत् तस्य कस्तस्मात् तदपोहति ॥ ४१४ ॥
A Sudra, though emancipated by his master, is not released from servitude; since that is innate in him, who can set him free from it?
english translation
na svAminA nisRSTo'pi zUdro dAsyAd vimucyate । nisargajaM hi tat tasya kastasmAt tadapohati ॥ 414 ॥
hk transliteration by Sanscript