21. The arrangement of communities in that world depends on their differences in love. The reason is that love is a person's life, and the Lord, being Divine love itself, arranges the communities in accordance with the way they receive that love. The differences between loves, which none but the Lord alone knows, are countless. The Lord links communities so that they all live as it were the life of a single individual. In the communities in the heavens this is a life of celestial and spiritual love; in those of the hells a life of devilish and hellish love, and He links the heavens and the hells by corresponding opposites. Because of this arrangement each person after death goes to join the community answering to his love, and he is unable to go anywhere else because of the opposing force of his love. This is why those having spiritual love are in heaven, and those with only natural love in hell. The only way to acquire spiritual love is by a life of charity, and natural love remains natural if a life of charity is neglected. Natural love, if not subordinated to spiritual love, is its opposite.