I spoke with the spirits around me about the fact that no one is perfect but the Lord Alone. The angels are not perfect, for Heaven is not holy before the Lord [cf. Job 15:15]; nevertheless, the angels can improve more and more, and even to eternity, yet never become holy in themselves, or as to what is their own. Because this struck spirits as odd when it had been pictured in a spiritual manner, it was therefore illustrated by similar occurrences in nature, specifically, that there are things approaching infinity, as they call it, yet which never reach it, like the asymtotes of a hyperbola;* but we may pass over these examples, since many do not understand them. Universal principles fall more readily under [the view of] the understanding. It was shown, moreover, that angelic minds are only instruments for receiving the beliefs of religion, and must therefore be developed; hence, that they grasp only the most general principles; but the details, which are infinite, even in every least object, can be filled in, although never completely, but only as to the most general ones, since the angels are finite instruments. So those details, when they are as it were inscribed by the Lord on their general principles, are what more and more perfect the angel; and because they can be filled in even to infinity, and the angel thus developed and perfected to infinity, he can never arrive at perfection, and therefore not at [a state of] holiness, so that heaven can never be holy in the Lord's sight. 1748, 19 February. * The manuscript has "parabola," but see Divine Providence 335.