Two verses, VII, 4 and VII, 5, where we are told that there are two Prakritis, where Sri Krishna says that He has two natures, not one nature but two natures. This itself is a surprising statement. Normally we think that everyone has one nature, but He says that, “I have got two natures”. And one nature is the lower nature, and the other is the higher nature. And the lower nature, He has described as consisting of eight elements: the five pañca mahā bhūtā(s); that is starting from ether, to air, to fire, to water, and to the earth. These are the five mahā bhūtā(s), and then mind, intellect, and egoism: these eight elements constitute the lower nature.
Now, there is higher nature, which is not described in full, but which will come later on; but here, Sri Krishna gives only two indications of what is the nature of this higher nature: first is jīvabhūtām; the one that has become the jīva;the higher nature which has become the jīva;yayedaṁ dhāryate jagat, and by which the world is upheld. That would mean: the principle of unity; to uphold the whole world is to uphold the oneness or unity of the world. You cannot uphold anything without unifying principle. So, one aspect of this nature, higher nature is: its power of unity. The other one is that it is that which has the stuff in the jīva.
Now, this concept of jīva is itself a very important concept in the whole of the Gita, and without this concept, we cannot deal properly with the problem of bondage and mokṣa. That is why the question that came was exactly at the right time. While we discuss the question of jīva, the question of the parā prakṛti, which has the nature of unity, it is at this time that we can deal with the question of bondage and liberation. Because bondage is related to aparā prakṛti, which is described earlier; mokṣa is related to parā prakṛti, which is described in the 5th verse. So, if you connect the 4th & the 5th verse, truly you get the answer both of bondage and of liberation. To be in bondage is to be in the aparā prakṛti, to be in liberation is to be in parā prakṛti.