Arcana Coelestia #61
61. Everything that has to do with cognitions of faith is called spiritual, and everything that has to do with love to the Lord and towards the neighbour is called celestial. The former belong to man's understanding, the latter to his will.
Apocalypse Explained #125
125. Be thou faithful even till death, signifies steadfastness in truths to the end. This is evident without explanation. It is said "even till death," because such as man is when he dies, such he remains to eternity; the life previously lived is only the life for the formation of his spirit (of which see many things in the work on Heaven and Hell 470-484).