agnostic

A person who holds to a form of agnosticism, especially uncertainty of the existence of a deity.

Of or relating to agnosticism or its adherents.

"His agnostic viewpoint is summarized in his book."

Doubtful or uncertain about the existence or demonstrability of God or other deity.

"She left the church when she became agnostic."

Of a software component etc.: unaware or noncommittal regarding the specific nature of the components or input with which it interacts.

"The socket communications layer is agnostic with regard to its underlying transport mechanism -- it is “transport-agnostic”."