Once a group of large hawks who were unable to find any prey attacked another, weaker hawk who was holding some meat. At that time, being in danger of his life, the hawk gave up his meat and experienced actual happiness.
Srimad Bhagavata Purana
श्रीमद्भागवतमहापुराणम्
मूल श्लोकः
सामिषं कुररं जघ्नुर्बलिनो ये निरामिषाः । तदामिषं परित्यज्य स सुखं समविन्दत
sāmiṣaṃ kuraraṃ jaghnurbalino ye nirāmiṣāḥ | tadāmiṣaṃ parityajya sa sukhaṃ samavindata
SB 11.9.2