Don't forget that few people are likely to tell more than a small part of the truth: no one tells much of the truth, let alone the whole truth. Spoken words are facts in themselves, whether true or false. When people talk they reveal themselves, whether they're lying or telling the truth.
No one has a monopoly of the true God, nor is there a nation or religion that can claim, or at any rate prove, that it has been given the exclusive right to the Creator or sole knowledge of His Being.