Leviticus 14:6

⁶ But the other that is alive he shall dip, with the cedar wood, and the scarlet and the hyssop, in the blood of the sparrow that is immolated:

Turtles, and young pigeons

In Genesis 15:9 and Leviticus 12:6, this signifies the good of innocence; the young pigeon, interior good, and the turtle-dove exterior good. (Apocalypse Explained 314) They also represent exterior and interior spiritual things. (Arcana Coelestia 1727)