'Spreading themselves on the earth,' as in Genesis 8:17, signifies the internal self operating on the external.

(Verweise: Arcana Coelestia 913)

8789. 'And let them wash their garments' means the purification of truths. This is clear from the meaning of 'washing' as an act representative of purification from spiritual filth, dealt with in 3147, 5954 (end); and from the meaning of 'garments' as truths, dealt with in 4545, 4763, 5248, 5319, 5954, 6914, 6918.