The Rama Gita is the fifth adhyaya of theUttarakanda of the well-known Adhyatma-Ramayana, which give the spiritual interpretation to the main incidents and personages occuring in the Srimad Ramayana.
The Rama gita contains Rama's spiritual message to his brother Lakshmana and contains the whole Vedantaic doctrine in a nutshell.
Originally translated by one of the monastic disciples of Sri Ramakrishma and the fourth president of the Ramakrishna Order. With Devamagri text and English translation.