In plain words
The body doing, the mind thinking, the Ātma being the witness. Though the duties of these three are of different kinds, though they move along separate paths, there is one thing common to them all: their resting on one another. Only when these three are inseparably joined can we make humanness worthwhile. The oneness of these three makes us follow the path called fullness.
Dharma, artha, kāma and Mokṣa are the puruṣārthas. Through this Dharma itself we must seek artha. Only when artha and kāma both rest on Dharma does this become worthwhile. When we let go of Dharma and crane after artha and kāma alone, our life falls prey to unrest. When artha and kāma follow Dharma, Mokṣa comes to us of itself. We can follow the easy path that says the waning of moha itself is Mokṣa. So humanness is not something newly formed only today. ‘Mā’ means ‘not’. ‘Nava’ means ‘new’. ‘Mānava’ means ‘this is not new’: that is its meaning. It is what has come from many births, old and stale. So if, however long it may be, we go on living our humanness only as old and stale, when are we to experience our true form? That is why we must show forth that form: all is Brahman. We must bring forth, in society itself, the Godhood whose form is everything. That is why: Īśāvāsyamidaṃ sarvam.
All the stars are Brahman; the sun is Brahman; the moon, too, is Brahman; water is Brahman; heaven, too, is Brahman; Vaikuṇṭha is Brahman; mother, too, is Brahman; father is Brahman; all wealth is Brahman; lordship is Brahman; all living beings are Brahman; the jīva is Brahman; to create is Brahman; to sustain is Brahman; to make to perish is Brahman; the housewife is Brahman; all of time is Brahman; the body is Brahman; all Prakṛti is Brahman; the life-breath is Brahman; everything is Brahman, and this gathering too is Brahman; making Satya known is Brahman; this Sai is Brahman.