What the punctuation in the title indicates:

Quotation marks: Draping the word God in quotation marks indicates that we are first concerned with the signifier, not the signified. (Compare these two sentences: I am interested in God. I am interested in “God.”)

Question mark: The mark of interrogation backstopping “God” points us next to questions concerning the concept or idea of God. What does it mean? Aren’t there many different meanings? Isn’t the meaning often vague or ambiguous?

The mark directs us further to questions concerning the existence of God. Is there any real entity denoted by the word God? Is there any way to conclusively answer this question?

A Lesson in Vedānta

The conception of God and the conception of Absolute Truth are not on the same level. The ÅšrÄ«mad Bhāgavatam hits on the target of the Absolute Truth. The conception of God indicates the controller, whereas the conception of the Absolute Truth indicates the summum bonum or the ultimate source of all energies. There is no difference of opinion about the personal feature of God as the controller because a controller cannot be impersonal. . . .  Because there are different controllers for different managerial positions, there may be many small gods . . . with various specific powers, but the Absolute Truth is one without a second. This ÅšrÄ«mad Bhāgavatam designates the Absolute Truth or the summum bonum as the param satyam.

The author of Śrīmad Bhāgavatam, Śrīla Vyāsadeva, first offers his respectful obeisances unto the param satyam (Absolute Truth), and because the param satyam is the ultimate source of all energies, the param satyam is the Supreme Person. The gods or the controllers are undoubtedly persons, but the param satyam from whom the gods derive powers of control is the Supreme Person. The Sanskrit word īśvara (controller) conveys the import of God, but the Supreme Person is called the parameśvara, or the supreme īśvara. The Supreme Person, or parameśvara, is the supreme conscious personality, and because He does not derive any power from any other source, He is supremely independent.

—ÅšrÄ«la Prabhupāda, Introduction to ÅšrÄ«mad Bhāgavatam

Where does everything come from?

Everything comes either from something or from nothing.

When the answer is nothing, it sometimes turns out to be a very special, hyper-potent kind of nothing. Not just nothing but Nothing. In other words, a unique kind of something (after all).

When the answer is nothing, it sometimes turns out to be a special inscrutable something, beyond all possible modes of understanding or investigation. Nothing is really a “No Trespassing” sign. (Or: “You don’t belong in the physics department; you should go to the religion department.”)

When the answer is nothing, it sometimes turns out that the “everything” that (seemingly) comes from it is really nothing also. Nothing makes no things: No problem!

Vedānta settles for something. A special unique something: param satyam или для писем есть brahman “the ultimate source of all energies.”janmādyasya yataḥ (Vedānta-sÅ«tra 1.1.2)

In the Upaniṣads, this ultimate source is described as so complete or full (purṇam) that however much is taken away from it, it remains complete.

By contrast, I am not purṇa. I am a dependent, contingent being. I require regular supplies—each day so much food, water, air, light, heat, and so on. If I trace back the supply chain I will reach (according to the Vedas) the empowered universal supply agents, the devas—lords of the sun, moon, wind, rain, soil, and so on.  As they distribute, their own stores becomes depleted, and they themselves need resupply.  Following back the chain of dependence, we reach finally a singular and unique being who produces endless supplies and who never needs resupply, remaining full. This the self-sustaining sustainer of all others is the param satyam.

(Think of the param satyam as something like a hotel with infinite rooms, all occupied—purṇa, “No Vacancy.” At noon, the guest occupying Room 1 checks out. As he leaves, the bellboy blows a whistle. All the rooms’ doors open: The guest in Room 2 moves into Room 1, the guest in Room 3 moves to Room 2, and so on, ad infinitum. Thus, even though a guest checked out, the hotel remains full. It will remain full if ten, a hundred, a thousand , a million, or even an infinite number of guests check out.)

This is the “concept of the Absolute Truth,” that from which everything comes. It differs from the concept of Ä«Å›vara or “god.” Īśvara means a controller. In that sense, even local controllers—the CEOs of SEPTA, PECO and Comcast, the president of the University of Pennsylvania, the mayor of Philadelphia, the governor of Pennsylvania, and so on—are all minor Ä«Å›varas, teeny gods with miniscule controlling power. And, according to the Vedas, there are superior gods who administer the universe—not petty bureaucrats but mighty cosmocrats.

Whatever we see here, in the effect, must also be there, in the ultimate cause. The param satyam has produced myriad personal controllers.  Therefore the ultimate personal controller, the parameÅ›vara, is in the Absolute Truth itself. The Upaniá¹£ads describe the param satyam as simultaneously personal and impersonal.

Prabhupāda coined the phrase “Supreme Personality of Godhead” to express more accurately the concept of Kṛṣṇa. The word “god” by itself is, strictly speaking, inadequate. A “god” is a being that may or may not exist. “Godhead” however, denotes the Absolute Truth, param brahman, the uncreated, self-sustaining origin of everything.  “Personality of Godhead” denotes the personal feature of the unlimited Godhead. The one Personality of Godhead exists simultaneously in many transcendent forms—Kṛṣṇa, Rāma, Ná¹›simha, Nārayaṇa, Vāmaṇa and so on.

Some argue that the limitless nature of the Absoute Truth precludes personhood, since personhood or individuality entails limits and boundaries. They forget to consider that it would also be a limitation to exclude personhood. There must be somehow pesonality without limitation. For this reason, Vedic thought understands the one Personality of Godhead to be ananta rūpam, expanded in unlimited forms simultaneously.

Among all these forms, Kṛṣṇa is particularly denoted “the Supreme Personality of Godhead.”

One last consideration: Should I find myself wondering whether the Personality of Godhead exists or not, then I should understand that I do not grasp the concept of the Absoute Truth. I am thinking of Godhead as if it were simply one more contingent, dependent being: like me, or my laptop, or my city. My Dell laptop exists, but it might not; RavÄ«ndra SvarÅ«pa dāsa exists, but might very well not; this City of Brotherly Love exists but might not have. My current controllers—Mayor Nutter, Governor Rendell, President Obama, Lord Indra, Lord Brahmā—are all there, but might not have been. But the final controller, the Personality of Godhead, the ultimate source of all energies, exists in a different way from all these other beings. He exists so fully or truly that he has not even the possibility of not existing.

If we simply understand the concept of the Absolute Truth, we must recognize that its mode of existence—existing without even the possibility of not existing—is different from ours.

(Perhaps some readers have recognized in the last paragraphs a version of “the ontological argument for the existence of God.” This argument has generated much controversy, yet it seems to me that Prabhupāda’s distinction between the concepts of God and of the Absolute Truth clairfies the argument and helps resolve some of the controversy. When one understands the argument as dealing with the concept of Godhead or Absolute Truth, rather than the concept of God, its particular force becomes more evident, at least to me. To me, there are sound and persuasive arguments that there must be an Absoute Truth, and that the Absolute Truth must be a person. I’ve outlined them above. That the person is blue-complexioned, flute-playing, peacock-feather-wearing Kṛṣṇa—or any expansions—cannot be shown by reason and logic. Only pareśānubhava, direct perception of the Lord, will disclose these concrete particulars. On the other hand, if one studies the Supreme Personality of Godhead as encountered by Nārada, Vyāsa, Uddhava, Caitanya, and so on, one can say: “This is our idea of the supreme person. Can anyone offer a description of any greater?”)