In class Prabhupada described the relationship of the living being with Krishna as "responsive cooperation." People sometimes ask, if God does not discriminate, then why are there rich and poor people in the world? The answer is that because of this responsive cooperation, however much we surrender to Krishna, that much He returns to us.
He explained how there are many men, who after making lakhs and crores of rupees, retire to Vrindavana. They leave all their money to their wives and families, requesting them to send two hundred rupees a month "for serving God." But this is not a good policy, he said. If we give two hundred to God, then Krishna will give us two hundred in return. He does not discriminate. Rather we discriminate, and Krishna reciprocates.
He offered himself as an example: "Just see practically. Our Krishna consciousness movement was started with forty rupees. Now that forty rupees added with Krishna, it has become forty crores. You see practically. When I started for your country, I came to Mayapur. I offered my obeisances to my spiritual master. Then I went. At that time I had no money even to purchase the ticket. And after that, I have come with forty crores. This is the secret. Ye yatha mam prapadyante. If you fully surrender to Krishna, then Krishna is there."
Reference: Transcendental Diary Volume 1
Author: Hari Sauri Dasa