In plain words
When you look at the mind with the eye of nature, it appears as matter. For this sorrow and this joy, for this matter and this energy, the mind alone is the cause. Taking the principle of these two as its ground, spirituality has declared, "Manayeva manuṣyāṇāṃ kāraṇaṃ bandhamokṣayoḥ."
What is purity? This very purity has been called power. And what is this power? They said that the absence of desire in man is itself purity. The moment desires arise, the shadow called sorrow comes too. Where sorrow enters, purity becomes a void. For both of these, the mind alone is the cause. There is the sight and there is the seen; only because there is sight can we see what is seen. And only because the seen is there can the eye see. So sight and the seen are bound together inseparably. But today sorrow begins precisely because we make the seen one thing and the seer another. Sight and the seen must become one. This is what the Veda declared: "Ekohaṃ bahusyāṃ prajāyeyeti." So the One has become the many. Recognise the One in the many.
Nations are many but earth is one Beings are many but breath is one Stars are many but sky is one
Seeing in this way, we see the many within the one that is.
Here there are three kinds of difference: sajātīya, vijātīya and svagata. What is sajātīya? Though our forms and our names are each our own, we are all the one human race. This is sajātīya. Taking this body as the ground, you, I, all of you, everyone is human. If you inquire into the oneness of all, without thinking of race, creed, age or name, you will know that humanity is one. This is sajātīya. An American, a Chinese, a man of any country at all, is a human being. This is sajātīya. Vijātīya means having no relation. You and the tree have no relation. You cannot say that the tree is of your kind. There is a difference between the race of trees and the race of men. This is vijātīya. Then there is svagata difference. In man there are many limbs: head, legs, hands, belly. Though these limbs are all there, each is separate in itself. One and the same blood flows through this whole body. The blood is one. The heart is one. Each part does its own functions. The eyes can see, but they do not try to hear. The ears hear, but they cannot see. Though the body is one, the limbs in the body do different work. This is svagata difference.