Bhagavad Gita 4.15
एवं ज्ञात्वा कृतं कर्म पूर्वैरपि मुमुक्षुभिः।
कुरु कर्मैव तस्मात्त्वं पूर्वैः पूर्वतरं कृतम्।।4.15।।
Evam gyatva kritam karma purvairapi mumukshubhih
Kuru karmaiva tasmattvam purvaih purvataram kritam
Simple meaning, written by AIHaving understood this, perform the duty just as the liberated ones before you have done; therefore, act, for the duty has already been performed by the ancestors.