Without God, we can not be free. On our own, we naturally seek our own security and happiness; that is, we become our own god. Since the world we live in is full of such little gods, conflicts and war are inevitable and our goal of finding happiness is doomed from the very beginning.
Now, if we live for God and not ourselves, we are no longer involved in seeking our own happiness ~ it is what pleases God that matters. When we and God are one, whatever pleases him pleases us, hence we are free! There will be no more fighting other little gods. This is absolutely true.