In a general sense, Swedenborg says mourning in the Bible represents a state of grief over the lack of desires for good and true ideas about life. This often happens when a church or an aspect of a church has fallen away from the Lord and has been devastated, with all its wisdom and leadership stripped away. It can also be when a new church or state of a church is soon to begin, and there is nothing yet in place.
In particular, especially when paired with “weeping,” Swedenborg says “mourning” has do with the loss of all desire for good and the presence of evil; “weeping” in those cases has to do with the devastation of thought and knowledge.
Passages from Swedenborg
Arcana Coelestia (Elliott) n. 4780
4780. ‘And mourned over his son many days’ means a state, namely one of mourning for lost good and truth. This is clear from the representation of Joseph, to whom ‘son’ refers here, as Divine Truth, specifically the truths spoken of above in 4776; and from the meaning of ‘days’ as states, dealt with in 23, 487, 488, 493, 893, 2788, 3785, in this case a state of great mourning since the expression ‘many days’ is used.
Apocalypse Explained (Tansley) n. 1164
1164. Weeping and mourning-That this signifies grief of soul and heart, is evident from the signification of weeping, which denotes grief of soul; and from the signification of mourning, which denotes grief of heart. The distinction between grief of soul and grief of heart is like that between truth and good. For soul in the Word is said of the truth which is of faith, and heart of the good which is of love. This is the reason why the expression, from the soul, and from the heart, frequently occurs in the Word. They are also distinguished as the will and the understanding in man, and also, as the respiration of the lungs and the motion of the heart. And because throughout the Word there is a marriage, as it were, of truth and good, or of faith and love, or of intellect and will, therefore it is also the case here with the expressions, weeping andmourning, weeping arising from grief of soul and mourning from grief of heart.
Arcana Coelestia (Elliott) n. 6540
6540. ‘And he made a mourning for his father seven days’ means the end of the grief. This is clear from the meaning of ‘mourning’ as the grief that is felt before cognitions of good and truth have been implanted, dealt with immediately above in 6539; and from the meaning of ‘seven days’ as an entire period from beginning to end, dealt with in 728, 1044, 3845, 6508, here therefore the end, because once that period of days had passed they crossed the Jordan.
Apocalypse Explained (Tansley) n. 1119
1119. So much give unto her torment and mourning.- That this signifies that they should have so much of infernal punishment and desolation, appears from the signification of torment, as denoting infernal punishment; and from the signification of mourning, as denoting desolation, which consists in their no longer possessing any truth and good, but merely falsity and evil. The reason why it is said that as much torment and mourning should be given her, as she hath glorified herself and lived delicately, is, that all torment or infernal punishment corresponds entirely to the evils in which they are.
Arcana Coelestia (Elliott) n. 2910
2910. ‘And Abraham came to mourn for Sarah and to weep for her’ means a state in which the Lord grieved, that is to say, because it was night as regards the truths of faith within the Church. This is clear from the representation of ‘Abraham’ as the Lord, dealt with in 1893, 1965, 1989, 2011, 2172, 2501, 2833, 2836. That ‘mourning’ and ‘weeping’ mean a state involving grief is clear without explanation. ‘Mourning’ has regard to grief on account of its being night as regards goods within the Church, and ‘weeping’ as regards truths. These two verses have dealt with the end of the Church, which arrives when charity does not exist any longer. The end of the Church is the subject many times in the Word, especially in the Prophets and in John, in the Book of Revelation. The Lord too in the Gospels describes that end extensively, calling it the close of the age, and also night.