"Ich glaube nicht an Gott."

Translation: I do not believe in God.

[lcmiracle]

Good sentence, well attested. We need more of these.

[Thrym]

Why is the "an" there?
Wouldn't that translate into: "I don't believe AT god"?

[Neotist]

You cannot say "an" always corresponds to "at" in English. In German certain verbs take certain propositions (just like in English) and these propositions are not always the same across the languages. You simply have to memorize them in each language.

[VeledaLorakeet]

No in this case "an" is pretty much meaning in. It is more expressing a connection really.