Like all the fruit of the spirit, it is a supernatural outworking of the Spirit of God within. If you are born again, peace abides within you. He gave it to you. We need to set our affections on eternal things. This will lead to peace.
Eternity is nothing but good news for the saved.
That's not to say that we ignore what is happening in our lives, but we need to take an eternal perspective on them. Now the God of hope fill you with all joy and peace in believing, that ye may abound in hope, through the power of the Holy Ghost. Again we see that peace is a supernatural outworking of salvation. It is the fruit of the spirit. It is not a conjured up emotional condition.