46. To distinguish them from the earth, presumably, in which they are rooted.

Unfinished Literal Commentary on Genesis 135
Genesis 1:1J: An additional work performed on the third day
11, 34. And God said: Let the earth sprout grass for fodder-bearing seed according to its kind and likeness, andfruit trees makingfruit, whose seed is in them according to their likeness (Gn 1:11). After the earth and sea were made and named and approved of (which as I have said often enough is not to be taken as involving intervals of time, in case the inexpressible ease with which God works should be limited by some kind of slowness), it does not immediately add, as with the two preceding days, there was made evening and there was made morning, a third day, but instead another work isjoined on, so that the earth may sprout grassforfodder-bearing seed according to its kindand likeness, andfruit trees makingfruit, whose seed is in them according to their likeness.
This was not said about the light and the solid structure and the waters and the dry land; that light, after all, does not have any progeny to succeed it, nor is another heaven born out of heaven, nor does earth or sea give birth to other seas and other earths, which are to succeed them. So here it had to say, bearing seed according to its kind and likeness, and whose seed is in it according to its like ness, where the likeness of the ones that are born preserves the likeness of the one that is passing away.
35. But all these things are on the earth in such a way that they cling to the earth with their roots and are continuous with it, and again are somehow separate from it. That's why I think this account has preserved the special significance of this kind of nature by having them made on the same day as the earth appeared, and yet once more saying, "God said that the earth was to sprout," and once more concluding, And thus it was made (Gn 1:11).
Next, according to the rule established above, after saying and thus it was made, it subjoins the actual carrying out of the work: And the earth produced grassforfodder-bearing seed according to its kind, andfruit trees makingfruit whose seed is in it according to its likeness; and again it says, Godsaw that it was good (Gn 1:12). And thus these works are both joined together in one day, and distinguished from each other by God's words being repeated. The reason I think this was not done with earth and sea is because there is a greater need to distinguish these other things,46 which propagate themselves by their seed when they spring up and then fall away.
Or is it that earth and sea could be made simultaneously, not only in the thoughts of the spiritual creation, where all things were made simultaneously, but also in the successive moving around of bodies, whereas trees and every kind of plant could not come into being unless the earth were there first for them to germinate in; and for that reason God's command had to be repeated, both to
46. To distinguish them from the earth, presumably, in which they are rooted.
