Calvin on the Knowledge of God (Part One)

In Chapter 3 of Book One of the Institutes of the Christian Religion, Calvin writes:

1. That there exists in the human minds and indeed by natural instinct, some sense of Deity, we hold to be beyond dispute, since God himself, to prevent any man from pretending ignorance, has endued all men with some idea of his Godhead, the memory of which he constantly renews and occasionally enlarges, that all to a man being aware that there is a God, and that he is their Maker, may be condemned by their own conscience when they neither worship him nor consecrate their lives to his service. Certainly, if there is any quarter where it may be supposed that God is unknown, the most likely for such an instance to exist is among the dullest tribes farthest removed from civilisation. But, as a heathen tells us, there is no nation so barbarous, no race so brutish, as not to be imbued with the conviction that there is a God.

Thus, every person, whatever his culture or background or religion, has some knowledge or instinct about God. And since there is but one true God, all people have some conception of him.

Does that then mean that they all "worship" the same God in some way? That remains to be further explored. I do not believe that Calvin makes this argument.