We say śānti three times at the end of a prayer. The Gītā asks one question: for one without peace, where is happiness?
Going deeper
Śānti is the word said three times at the end of a prayer, and 2.66 asks what peace depends on. For the person who is not integrated, it says, there is no settled understanding and no contemplation of the self, and without contemplation there is no peace. And for one who lacks peace, where is happiness? The verse before, 2.65, says that in serenity all sorrow is lost. The verse after, 2.67, describes the opposite: when the mind follows the roaming senses, it carries away the understanding, as the wind carries a ship on the water. Together the three verses form a chain. A settled mind leads to peace, peace to happiness, and a mind dragged along by the senses loses all of it. The Gītā's own question is a plain one, and it can be answered by looking at your own state. The passage is in chapter 2.