Verse
एवं ज्ञात्वा कृतं कर्म पूर्वैरपि मुमुक्षुभिः ।कुरु कर्मैव तस्मात्त्वं पूर्वैः पूर्वतरं कृतम् ॥
So knowing was work done by the men of old who sought liberation; do therefore, thou also, work of that more ancient kind done by ancient men.
Gītā 4·15