In plain words
Only in the worldly view do we imagine we have offered something to God. We think that only then do Śānti and happiness come to us. With this in view, in the Veda: Na karmaṇā na prajayā dhanena tyāgenaike amṛtatvam ānasu. What is the inner meaning of saying that immortality comes to us through sacrifice? So we must sacrifice individuality. We must develop the sense of the collective. We must enter into society. We must serve the Lord of all who is in society. For how can man, who cannot see the vast principle of Jñāna, man who cannot enter the innermost depths of life, achieve the peace of the world? The peace of the world rests on the peace of society. The peace of society rests on the individual. Only when the individual is in Śānti can we shape society into the form of peace. Only when society is in peace and security will the whole country be filled with peace and security. So the individual, society and the universe, these three, are forms whose nature is that of the Trimūrti. They are supports of one another. They are bound in an inseparable relation. So we must develop the Ānanda of the individual. We must fill society with this Ānanda. With the Ānanda that has filled society we must pervade the whole world. You must not selfishly hoard all your Śānti and happiness. We must not lead our life as a life cut off and alone, merely like a drop of water poured on oil or a drop of oil laid on water. You must hate no one. This is the very essence of the Bhagavad Gītā. Adveṣṭā sarvabhūtānām. Whomever you hate, you are the one who has hated yourself. Do not think of a narrow family of only this much: my mother, my father, my elder sister, my younger sister, my sons, my wife. You must look on yours as the family of the world. You must make your heart broad. Only then can God dwell in that broad heart itself. To foster such broad feelings, they have gone on teaching, through yajñas, yāgas and such rites, the spirit of sacrifice and the way to give up individuality.
The very words the maharṣis of those days spoke turned into mantras. Mantras are not one thing and words another. Every sound that came forth from a holy heart took the form of a mantra.