You subsist by eating grains. Of course, now . . . nowadays we have invented so many artificial foodstuff. But however artificially foodstuff, however flesh and other things we may take, without grains we cannot live. The grains must be there. The wheat and the rice and the paddy and the cereals, there must be there. So real . . . real foodstuff is anna. Anna means this grain.
So by eating grains we subsist. Our life prolongs by eating grains. So annād bhavanti bhūtāni parjanyād anna-sambhavaḥ. And grains are produced by proper rainfall. Rainfall is the main source of producing everything of our necessities of life. Without rainfall we cannot produce anything of the necessities of life.
We have got many necessities of life, not only grains. We require cotton for clothing. We require silk for luxury. We require valuable stones and jewels. All these are produced under certain circumstances of rain. Rain is falling on the sea and the ocean also. So there is purpose. Under certain constellation of the star, if the rain falls on the sea, it produces pearls and jewels. We have got this information from Vedic literature. So everything is produced, whatever you require.
Now, pasturing ground for the cows—the grass is produced by rains, and the animals, they eat the grass and they produce milk. You require milk. So everything, the main source of supply is the rainfall from the sky. That is not under your control. So Bhagavad-gītā says, parjanyād anna-sambhavaḥ. Without rain, you cannot have any production. Nothing can be produced without rain.
And without production, you cannot live. But rain, regular rain and regulative rain and useful rain, will fall when you perform sacrifices, yajña. Yajñād bhavati parjanyaḥ (BG 3.14). And yajñaḥ karma-samudbhavaḥ: and you can perform yajña by working. Because yajña requires materials, so if you have no money, if you don't work, you cannot have money. So everything is a circle. It is nice circle.
Karma brahmodbhavam. And how to work, that is described in the Vedic injunction, that "You should work like this." We have all discussed. Niyataṁ kuru karma tvaṁ karma jyāyo hy akarmaṇaḥ (BG 3.8).
So everyone has some prescribed duties. There are different classes of men. The intelligent class of men, the administrative class of men, the productive class of men, the laborer class of men—everyone has to work. And by working, by the result of the work, one has to perform yajña. And by regular performance of yajña, there will be regular rains. And by regular rains, there will be production sufficient to supply your necessities of life. So that is the circle. That is the circle.