Bhagavad Gita 11.55मत्कर्मकृन्मत्परमो मद्भक्तः सङ्गवर्जितः।निर्वैरः सर्वभूतेषु यः स मामेति पाण्डव ॥

This is the essence of the whole teaching of the Gita. He who practises this teaching will attain Supreme Bliss and Immortality. This verse contains the summary of the entire philosophy of the Gita.He who performs actions (duties) for the sake of the Lord, who consecrates all his actions to Him, who serves the Lord with his heart and soul, who regards the Lord as his supreme goal, who lives for Him alone, who works for Him alone, who sees the Lord in everything, who sees the whole world as the Cosmic Form of the Lord and therefore cherishes no feeling of hatred or enmity towards any creature even when great injury has been done by others to him, who has no attachment or love to wealth, children, wife, friends and relatives, and who seeks nothing else but the Lord, realises Him and enters into His Being. He becomes one with Him.