This verse is from the Bhagavad Gita, Chapter 6, Verse 7. It is written in Sanskrit and translates to English as follows:
jitātmanaḥ praśhāntasya paramātmā samāhitaḥ
śhītoṣhṇa-sukha-duḥkheṣhu tathā mānāpamānayoḥ
"He who has conquered the mind, has obtained tranquility; the Supreme Self remains unmoved by pleasure and pain, cold and heat, honor and dishonor alike."
jitātmanaḥ - of one who has conquered the mind
praśāntasya - for the tranquil
paramātmā - the Supreme Self
samāhitaḥ - remains steadfast
śītoṣṇa-sukha-duḥkheṣu - in cold and heat, pleasure and pain
tathā)- as well as
mānāpamānayoḥ - in honor and dishonor