Truth, Semantics, and Meaning: What does it mean to assert that something is true? A very popular answer is map-territory correspondence theory. But the details of this theory are not clear, and there are other contenders.
Many consider truth as the correspondence between reality and one's beliefs about reality. Within this frame, truth itself is not necessarily limited to one's belief about something. For a statement/ideal/proposed fact to be considered "true," you must take it as its definition. Truth doesn't imply that something has to be proven in order for it to be made true, but that the statement/ideal/proposed fact has to be true all of the time, regardless of one's belief.
Alfred Tarski defined truth in terms of an infinite family of sentences such as:
The sentence 'snow is white' is true if and only if snow is white.
To understand whether a belief is true, we need (only) to understand what possible states of the world would make it true or false, and then ask directly about the world. Often, people assume that ideals and morals change with culture; as they tend to do. Unfortunately, many people struggle with their belief of "truth" based on their religion. Because of their belief, they object the currently accepted "truth" about the world, about life (how we all got here), and most importantly, what is considered "right" or "wrong."
"Truth" is not, however, a determination. Truth is not simply a belief. Truth is an ideal, concept, or fact that can be observed. Whether an individual has a belief derived from their religion on what is truth or not, unless they have observed it, they cannot prove whether their belief is truth or not. Reiterating from above: the lack of proof or justification, or even rationalization, does not change the status of truth. What's truth is truth, and what is false, is false. Humans simply decide to reject notions and proposed facts as truth if they are not observable, or are not able to show any proof.
'Truth' is a very simple concept, understood perfectly well by three-year-olds, but often made unnecessarily complicated by adults.
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