18.1 saṅnyāsasya of renunciation, mahābāhō O mighty-armed, tattvam the essence of truth, icchāmi (I) wish, vēditum to know, tyāgasya of Tyaga or abandonment, ca and, hṛṣīkēśaḥ O Krishna, pṛthak severally, kēśiniṣūdan slayer of Kesi.

Commentary:
The teaching of the whole of the Gita-Sastra is summed up beautifully in this discourse. This last discourse is a brief masterly summary of all that is told in the previous chapters. Arjuna wishes to know the distinction between Sannyasa and Tyaga.Kesi was an Asura whom Lord Krishna slew. So, Lord Krishna is addressed as Kesinishudana by Arjuna.The words Sannyasa and Tyaga have been used here and there in the preceding discourses, but their connotations are not lucidly distinguished. Therefore Lord Krishna clearly explains to Arjuna the right significance of the two terms in the following verse.