'Grass' is natural truth, and 'flower of the field' is spiritual truth, as in Isaiah 40:5, 6. Green grass, in the Word, signifies the good and truth of the church, and of faith, which first springs up in the natural man. This is also signified by 'herb in the field.' Grass and the pulse of the herb, as in Psalm 32:2, signify what is most vile. Grass signifies science from a spiritual origin, or that by which spiritual truth is confirmed. 'Reeds and rushes' signify science from a sensory origin, or the things which confirm the fallacies of the senses, as in Isaiah 25:7. This science, considered in itself, is only a part of the lowest natural degree, which may be justly called material and bodily, in which there is little or no life. Green grass also signifies that which is alive with man. 'Grass burnt up' signifies the things which are dead in him. Grass signifies the scientific principle. Just as green grass serves animals for support, spiritual truth serves men for spiritual nourishment.

(References: Apocalypse Explained 507)

4. As long as the mind confines itself to the sense of the letter alone one cannot possibly see that its contents are such. Take for instance these first sections of Genesis: From the sense of the letter the only subject matter people recognize is the creation of the world, and the Garden of Eden which is called Paradise, and Adam as the first man to be created. Who thinks anything different? The fact that these things contain arcana however which have never been revealed up to now will be sufficiently clear from what follows - especially clear from the fact that the subject of Genesis 1 is, in the internal sense, the NEW CREATION of man, that is, in general his REGENERATION, and in particular the Most Ancient Church. And the subject is presented in such a way that not the smallest part of any expression fails to have a representation, carry a spiritual meaning, or embody something within itself.