In the past, peace meant a time without wars, fighting, or the threat of violence. Today, peace is used to refer to a state of harmony, quiet, or calm with no hostility.
Being mentally and spiritually at peace means that you truly know yourself and what you are capable of, and you do not waste your time or energy on things that are unimportant or meaningless.
"If someone thinks that peace and love are just a cliche that must have been left behind in the 60s, that’s a problem. Peace and love are eternal." - John Lennon “Never be in a hurry; do everything quietly and in a calm spirit. Do not lose your inner peace for anything whatsoever, even if your whole world seems upset.” —Saint Francis