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12 And the earth brought forth grass, and herb yielding seed after his kind, and the tree yielding fruit, whose seed was in itself, after his kind: and God saw that it was good.
"Birds" represent rational concepts in the external man and intellectual concepts in the internal man.
11 How much more, when wicked men have slain a righteous person in his own house upon his bed? shall I not therefore now require his blood of your hand, and take you away from the earth?