I don't have your quote, but I may have the original version:
Out of the night that covers me,
Black as the Pit from pole to pole,
I thank whatever gods may be
For my unconquerable soul.
In the fell clutch of circumstance
I have not winced nor cried aloud.
...
Paul is arguing that anyone who looks at God's creation in an intelligent and sympathetic way must acknowledge the existence of a powerful creator.
Dummelow's commentary expresses it this way: "His power and divinity are so clearly impressed upon the visible creation that they [the Gentiles...