Your beliefs are not my beliefs. My beliefs are not your beliefs. Everyone has different beliefs that not everyone agrees with, and that's a fact. Funny thing about facts: They don't care if you believe them or not. Truth is true, no matter who believes it's false. Lies are lies, no matter who believes they are true. Majority or minority, wise or foolish, rich or poor, king or commoner, we all inhabit the exact same reality.
Because of this, not all beliefs are equal. You cannot justify a belief you like just by saying "I believe it" or "they believe it". You cannot refute a belief you don't like by saying "that's just your belief" or "not everyone agrees", or even "keep your opinions to yourself you hateful bigot!"
Yet, somehow, in our world of "tolerance", Christian apologists hear this sort of thing all the time. But really, it's absurd to argue this way. Imagine the following conversation between a flat earther (they're gaining ground) and a round earther:
Round Earther: The world is round.
Flat Earther: That's just your belief. Not everyone agrees.
RE: Those who disagree are wrong.
FE: You're a hateful bigot!
RE: No, I don't hate you, and you're free to believe what you want, but the earth is round.
FE: Keep your opinions to yourself!
RE: Why? You're allowed to voice yours, I'm allowed to voice mine.
FE: But you're wrong!
RE: That's just your belief. Not everyone agrees.
There are several observations that can be made from the above conversation.
1. They cannot both be right. Either the earth is round, the earth is flat, or the earth is a different shape all together. A maximum of one debater can be correct.
2. Neither man was any more, or less, informed about the other's position by the end of this dialogue.
3. No facts were discussed during this dialogue either. Neither side backed their claims with evidence because they were too busy bickering about the validity of such a discussion in the first place.
4. The argument can go both ways. The flat earther used it first, then the round earther managed to swing it around.
5. The flat earther did not even live consistently with their Relativistic beliefs. Whereas he is quite happy to voice his opinions freely, he insists his detractors not do the same, even under the guise of such detractors being hateful.
Ultimately, Relativism adds nothing but chaos to our world. Rather than working together to improve the world in which we live, we preach a message that we are all free to follow our own delusions, and no one (especially Christians) has the right to tell us a truth we don't like, because that's "hate speech". But who does this absurd philosophy really help? No one! If Relativism worked, we could cure the world's most deadly diseases simply by accusing anyone who believes in them of being bigoted.
But however much we may wish, or agree, or even agree to disagree, there is a very real truth. A reality which, accept or reject, is true nonetheless. That truth is that there is a God, the Creator of our universe, our species, and everything down to the very last letter of our genetic code. We have sinned against that God, and a time will come when we will die, and stand before Him in judgement. The penalty for our sins? Eternal punishment.
But a greater truth exists, as well. This same God, though He must punish sin, does not have to punish the sinner. Rather, He chose to send His son, Jesus, to live a perfect life as a man, a life which was ended by the most brutal form of capital punishment humanity has ever invented. Jesus died the death you deserve, then He rose again from the dead. Because of this, our sins can be completely forgiven, and when we stand before God in judgement, He can legally dismiss our case and grant us eternal life in His Kingdom. How might you obtain this, you ask? Simple: Believe that truth. Believe that Jesus, the Son of God, took your punishment for sin so that you may be rewarded for His righteousness. For God, that belief (called faith) is sufficient to cover you with that grace.