From Arcana Coelestia ~ Emanuel SwedenborgWhat peace is ... it is like dawn on the earth, which gladdens minds with universal delight; and the truth of peace is like the light of the dawn. This truth, which is called "the truth of peace," is the very Divine truth in heaven from the Lord, which universally affects all who are there, and makes heaven to be heaven; for peace has in it confidence in the Lord, that He directs all things, and provides all things, and that He leads to a good end. When a man is in this faith, he is in peace, for he then fears nothing, and no solicitude about things to come disquiets him. A man comes into this state in proportion as he comes into love to the Lord.
All evil, especially self-confidence, takes away a state of peace. It is believed that an evil person is at peace when he is in gladness and tranquility because all things succeed with him. But this is not peace; it is the delight and tranquillity of cupidities, which counterfeit a state of peace. But in the other life this delight, being opposite to the delight of peace, is turned into what is undelightful, for this lies hidden within it. In the other life the exteriors are successively unfolded even to the inmosts, and peace is the inmost in all delight, even in what is undelightful with the man who is in good. So far therefore as he puts off what is external, so far a state of peace is revealed, and so far he is affected with satisfaction, blessedness, and happiness, the origin of which is from the Lord Himself.
Concerning the state of peace which prevails in heaven it can be said that it is such as cannot be described by any words, neither, so long as he is in the world, can it come into the thought and perception of man, by means of any idea derived from the world. It is then above all sense. Tranquility of mind, content, and gladness from success, are relatively nothing; for these affect only his externals; whereas peace affects the inmost things of all-the first substances, and the beginnings of substances in the man, and therefrom distributes and pours itself forth into the substantiates and derivatives, and affects them with pleasantness; and affects the origins of ideas, consequently the man's ends of life, with satisfaction and happiness; and thus makes the mind of the man a heaven.
(Arcana Coelestia 8455)