* Creideamh i nDia: This is a very literal translation, meaning "belief in God." It's a good general option.
* Creideamh Dé: This translates to "God's belief" or "belief of God," but it's often understood to mean "faith in God" or even "God's faith" in the context of a discussion about faith.
* Muinín i nDia: This translates to "trust in God," which is a closely related concept to faith.
The best option depends on the context. If you want a direct equivalent of "belief," `Creideamh i nDia` is excellent. If you want to emphasize trust, `Muinín i nDia` is more suitable. `Creideamh Dé` is a slightly more poetic and less literal option.