Heaven" and "heavens" are used many times in the Bible, with a couple of variations of meaning. Sometimes it is relatively literal, including times when the Lord is identified with it (“Our Father, who art in the heavens,” for instance), meaning heaven as the eternal home for people who chose to do what is good in this life and let the Lord lead them to a love of being good. In other references, particularly when it is paired with “earth” or other lesser ideas (“In the beginning God created the heavens and the earth,” for instance), “heaven” or “heavens” means our internal life as opposed to our external life. In a way, these two meanings are really the same. If you think about the importance of your deepest thoughts and feelings, you can see that they are the “real” you, much more so than your body is. The relationship between the spiritual world and the natural world is similar; the spiritual world is the “real” one, and controls the natural world the same way our thoughts and feeling control our actions. So in both cases, “heaven” describes a deeper reality that we will enter fully after we die.

58. Verse 30 And to every wild animal of the earth and to every bird of the air, ¹ and to everything creeping over the earth in which there is a living soul [I give] every plant for food; and it was so.

The natural food of this same [spiritual man] is being described here. His natural level is here meant by 'wild animal of the earth' and by 'bird of the air, to which 'the edible and green plant ² has been given for food'. Both kinds of food, natural and spiritual, are referred to in David as follows,

Jehovah causes the grass to grow for the beast, and the plant for man's service, that he may bring forth bread from the earth. Psalms 104:14.

Here 'beast' stands for both wild animals of the earth and birds of the air, ¹ both being mentioned in verses 11-12 of that Psalm.

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