(Prabhupada's lecture - Śrīmad-Bhāgavatam 1.16.12 - Los Angeles, January 9, 1974)
So what is that religion? That is also explained in the Bhagavad-gītā. Sarva-dharmān parityajya mām ekam [Bg. 18.66]. This is religion, to surrender to God. It doesn't matter what religion you profess. It doesn't matter. But you must learn how to obey the Supreme Lord. That is religion. Religion does not mean that you stamp some stereotype religion, "I am Christian," "I am Hindu," "I am Muslim," "I am Buddhist," and then fight. That is not religion. That is fanaticism. Religion means how one has become devoted to God. That is religion. Sa vai puṁsāṁ paro dharmo yato bhaktir adhokṣaje [SB 1.2.6]. You claim to be religious, or you claim to be Hindu or Christian or Buddhist. That's all right. But do you know what is God? Oh, everyone silent. Everyone, all nonsense rascals, silent. He does not know what is God. And what is his religion?
If you do not know what is God, a vague idea, that is not religion. You must know what is God. Just like to become American citizen, it requires to know something of the history of America. So if American citizen, if you ask him, "What you are?" "Now I am American." "Who is your president?" "I do not know." What is this nonsense, American? Would you like to hear from him that "I do not know who is president"? Similarly, a human being professing some certain type of religion, but you ask him, "What is God?" Religion must be in relationship with God, any religion. But ask him, "What is God?" No answer. But religion means,
sa vai puṁsāṁ paro dharmo
yato bhaktir adhokṣaje
ahaituky apratihatā
yayātmā suprasīdati
[SB 1.2.6]
This is religion, first-class religion. What is that first-class religion? Yato bhaktir adhokṣaje, by practicing which one becomes a devotee of the Lord. That is religion. That is religion. So instead of becoming devotee of the Lord, we are devotee of dog. This is our position.