Yes there are standards.
If I believe the sun will set tonight there is astronomical evidence, photographic evidence from space, and the evidence of common sense: “It always has set!”
If I believe that someone is my mother (for instance), then all the years I’ve spent with this person, and records of birth, and photographs, and the kind of relationship we have, are all evidence which make the statement worthy of belief.
There is evidence for faith too, but because faith in God is faith in an infinite and eternal person, the evidence is of a different order. Only God Himself can present the evidence necessary to believe in him, even though the whole created universe cries out in testimony, because there is no image, no concept and no experience (on the purely natural level) which can do any justice to God.
This is why we are asked by the new testament, to “live by faith,”–it is only by first opening our minds and hearts to the possibility of God’s existence, and entreating him in his utterly inaccessible infinity, to make himself present to us: which is prayer and petition (!!), that we can have “the instrument” to gather the evidence for right belief in God.
The instrument we use to believe in God is our very selves; the laboratory in which we conduct the experiment of divinity, is the whole of our being: body, mind, soul and humanity.
(( at the same time, right faith has the corollary persuasive evidence (not demonstrative) that it does not contradict the findings nor the principles of natural human reason–but in fact enlightens them.))