In Leviticus 11:7 and Matthew 7:6, this signifies filthy loves of those in the hells of adulterers. (Apocalypse Explained 1044[4]) Swine signify people who love only worldly riches. (Apocalypse Revealed 727)

In Isaiah 65:4, this signifies appropriation of infernal evils. (Apocalypse Explained 659[2]) 'Swine' or 'hogs' correspond to the life of greed and its delight.

(References: Arcana Coelestia 1742)

1826. That 'he took a turtle dove and a fledgling' means those things that are [the representatives] of the spiritual things of the Church is clear from the meaning of birds in general, and of turtle doves and pigeons in particular. That 'birds' means spiritual things, which are more matters of faith or truth, and so means intellectual concepts and rational concepts, has been shown already in 40, 745, 776, 991; and that 'pigeons' means the goods and truths of faith, 870. And in addition to this, what the birds used in sacrifices meant is in the Lord's Divine mercy to be discussed later on where sacrifices are the subject. When in the Word, especially the Prophetical, celestial things are spoken of, so also are spiritual things spoken of, and thus the two are joined together, for one derives from the other, so that one belongs to the other, as stated already in 639, 680, 683, 707, 793, 810.