śrīmadbhagavadgītā - What is tyāga?
yajña-dāna-tapaḥ-karma na tyājyaṁ kāryam eva tat
yajño dānaṁ tapaścaiva pāvanāni manīṣiṇām ||18.05 ||
etānyapi tu karmāṇi saṅgaṁ tyaktvā phalāni ca
kartavyānīti me pārtha niścitaṁ matam uttamam ||18.06 ||
Re-ordered word-by-word meaning
yajña-dāna-tapaḥ-karma na tyājyaṁ - Acts of worship through work, acts of charity, and obeservance of austerity are not to be given up.
kāryam eva tat - that should be done without fail as,
yajño dānaṁ tapaś caiva pāvanāni manīṣiṇām - these acts of worship, charity and austerity purify and uplift all mankind.
pārtha me niścitaṁ uttamam matam iti - Oh Arjuna, my decided and supreme opinion is that,
tu etāni api karmāṇi kartavyāni - even these acts should be performed
saṅgaṁ tyaktvā phalāni ca - without attachment (ie without ego and likes and dislikes), and no attachment to the results or gains there from.
I am attending the 18th Chapter discourses by Pujya Swami Tejomayananda of Chinmaya Mission at NMKRV auditorium 11-21 November. Wonderful insights and the entire experience is very uplifting.
As Swamiji said, the 18th chapter is the summary or debrief of the entire Gita. In that the very first subject taken up is the idea of non-attachment or Tyaga. Swaimiji clarified that the trio of Tapas, Yagna and Dana mean as follows:
Tapas: bring your entire mind, senses, organs of action, ie the entire being, into a single pointed focus.
Yagna: Using that focus, perform your actions with a grand vision for the welfare of all.
Dana: Such a performance is bound to yield rich results, as is the law of nature. But these results or fruits, should be shared with all, with no attachment or possessiveness.
The ideal cited is that of the tree. It grows, and produces the best of fruits, only to be shared entirely with the world, holding nothing back for itself.
