ज्ञातमेतन्मया ब्रह्मन्यथास्मिन्भुवनत्रये ।मन एव हि संसारिजरामरणभाजनम्
In plain words
Rāma said: This I have understood, O brāhmaṇa: that in this triple world it is the mind alone, indeed, that is the vessel of the transmigrating one's old age and death.