Verse
स्वे स्वे कर्मण्यभिरतः संसिद्धिं लभते नरः ।स्वकर्मनिरतः सिद्धिं यथा विन्दति तच्छृणु ॥
A man who is intent on his own natural work attains perfection. Listen thou how perfection is won by him who is intent on his own natural work.
Gītā 18·45