Sometimes, I hear someone say something to the effect of “God is invisible, therefore evidence for Him is different from evidence for other things.” This is often encapsulated by an argument for faith-in-the-existence-of-God, where this faith is understood to be a choice made in the absence of a certain threshold of evidence, such as the ‘hidden God’ argument.
The problem with this line of thinking is that many (most) things are invisible. Gravity is invisible, for example. There are effects on visible objects (an apple, say), and we infer a cause (gravity).
Strictly speaking, we never directly see most anything – rather, we see light that is reflecting off or emanating from objects. The objects themselves are inferred. Even light is an inference – we have various experiences, and from these we infer there is something, ‘light’, which in some way is interacting with our eyes.
Gravity is invisible in the sense of ‘being detectable only by its effects on other things’ , but it is not therefore in some unique epistemic situation vis a vis other things in the natural world, or sciences. Consider earthquakes, or magnetic fields, or sounds, and so on. Similarly, just because God is invisible doesn’t mean there is some unique evidential situation vis a vis other postulated causes.
Put briefly, God is visible through His effects.