In plain words
In this, humanness lies within divinity itself. The root of the outer world and the source of the inner world: that is the principle of the Ātma. Man is forgetting this principle of the Ātma. Yet the physical body is like an armour for the mind. Taking the body alone, made of the five elements, to be everything and the support of the world, he has gone on following it. This is great ignorance.
Man needs sādhana
The mind, in its nature, has arisen from the body. The body is annamaya. From the annamaya it enters the prāṇamaya kośa. The prāṇamaya kośa merges into the manomaya kośa. The food man eats changes in three ways. The gross matter he passes out as waste. The subtle part of the food turns into muscle. The subtlest part of the food turns into mind. In the same way, the gross part of the water he drinks goes out as urine. The subtle part turns into blood. The subtlest part turns into prāṇa. The food and water man takes in assume the prāṇamaya and manomaya forms. The body is made of the five elements. It is like a bubble on water. It is impermanent and transient. It is subject to the six changes: being born, growing, being nourished, developing, declining and perishing. The prāṇa and the mind that arise from this body of six changes are themselves subject to the six changes! Just as the body is impermanent, so too prāṇa is impermanent! The mind is more impermanent still. The mind is fleeting; it wavers from moment to moment. It runs faster even than the speed of light. So no one can control the running of the mind. This mind envelops the whole world. To strive to make such a sacred mind vijñānamaya: that is right education.