There is no understanding for the undisciplined, and for the undisciplined there is no meditation; for the unmeditative there is no peace, and for the man who has no peace, how can there be happiness?
He attains peace into whom all desires enter as waters enter the ocean which, filled from all sides, remains unmoved; but not the man who is full of desires.
That man attains peace who, abandoning all desires, moves about without longing, without the sense of mine and without egoism.
He who knows Me as the enjoyer of sacrifices and austerities, the great Lord of all the worlds and the friend of all beings, attains to peace.
The Supreme Self of him who is self-controlled and peaceful is balanced in cold and heat, pleasure and pain, as also in honour and dishonour.
The man who is full of faith, who is devoted to it, and who has subdued the senses obtains (this) knowledge; and having obtained the knowledge he attains at once to the supreme peace.
This text is already in English. It appears to be a commentary or explanation rather than a direct translation from Sanskrit or another language.
If you have a Sanskrit verse (shloka) from the Bhagavad Gita that you'd like me to translate into English, please share it, and I'll provide the authentic English translation of its meaning.