In plain words
Because this yajña was held in the forest, villagers and town-dwellers from all around alike would come to that place and, in a spot that was equal for all, share in the yajña with a pure heart. The teaching of those days was that to perform a yajña by begging from someone is not sacred. Every single person going to the yajña would take along a handful of the nine grains and bury it in one spot, and with those very nine grains they used to carry out the yajña. The maharṣis of those days would mix together in one place all the nine grains these people had brought (the inner meaning of this: making the hearts of all one), and by that means set about performing the homa. The ṛtviks too would bring as many samidhs as they could, put them together and perform the yajña and homa. So in those days its fruit reached everyone equally. This was the very sacredness of the yajñas of those days. Today, because selfishness, individualism and self-regard have grown too great, the very sacredness of the yajña has come to nothing. Because Ahaṅkāra, self-regard and selfishness have grown so strong, even the sacredness of the yajña is no longer seen by us at all. That is why today the thing called yajña appears to the world in a form that is laughable.
These yajñas are of two kinds: the inner yajña and the outer yajña. The outer yajña is nothing but the reflection of the inner yajña! In view of time, karma, task and duty, in today's conditions they take the very reflection of the yajña, turned outward, to be the inward one! The yajña turned inward is the bird held in the hand; the yajña turned outward is the bird in the bush. But the bird in the bush is only the reflection of the bird in the hand! Today, because the sacred atmosphere has been lost, they let go of the bird in the hand. People are scrambling after the bird in the bush. In sum, it is most urgent that every single person recognise the sacredness of the inner yajñas.
The inner yajña means just this: through worship, to experience the divinity that lies hidden in us, secret and concealed. In every human being divinity is always shining, blazing bright. To offer up to that God, on the altar of the yajña called the Manas, the beastliness in us called evil qualities: that is the true essence of the yajña. By nature, man is not born as a man straight away. From many kinds of animal births, this humanity comes to us at the very last. The vāsanās, qualities and ways of behaving of old births remain in man. If a sore comes up on the hand, even after the sore has healed a scar remains to some extent. In just the same way the saṃskāras of former births remain in this birth.
What is the sign of this? What is the proof of this? In man, the thing called arrogance torments him, to some degree at least. This arrogance is not a quality of man. It is the quality of the elephant. So in a former birth, some time or other, we were an elephant, and its quality remains in us, more or less. The second is what is called foolishness.