Bhagavad Gita · Chapter 4: Knowledge and the Renouncing of Action

Bhagavad Gita 4.31

yajñaśiṣṭāmṛtabhujo yānti brahma sanātanam | nāyaṃ loko'styayajñasya kuto'nyaḥ kurusattama ||

Those who eat the nectar that remains after sacrifice go to the eternal Brahman. This world is not for one who makes no sacrifice; how then could the next be, best of the Kurus?

Modern context

What is left after giving is called nectar. Food eaten after others have been fed, and money enjoyed after one's obligations have been met, taste different from what is seized first. The second line is blunt. A person who gives nothing does not even do well in this world, let alone any other. A life organised wholly around taking ends up lonely and joyless, and people can see it. Some form of giving is a condition of ordinary happiness, quite apart from any spiritual reward.