Mahabharata 3.2.25

मानसं शमयेत्तस्माज्ज्ञानेनाग्निमिवाम्बुनाप्रशान्ते मानसे दुःखे शारीरमुपशाम्यति

mānasaṃ śamayettasmājjñānenāgnimivāmbunāpraśānte mānase duḥkhe śārīramupaśāmyati

Our plain-language meaning of this verse is waiting for scholar review.