AllTimeJeff,
I can agree with some of this. Out of respect for your faith, I do not wish to discuss why you believe that Jesus is the "truth" for you. It doesn't have to be a topic for conversation. I would take exception if you thought that Jesus is the truth for me. He isn't. Also, I don't agree with your statement that such a faith must be universal. It starts, not on what is true, but what is believed, by definition, an article of faith. Again, I don't begrudge you this, but cannot in any way call it truth. It isn't true, nor universal. It's not even totally terrestrial, as evidenced by the other religions on the earth.
Perhaps we speak from different perspectives. Having studied eastern religions, such as Daoism (Taoism), Shintoism, Buddhism, Hinduism, and Confucianism (more of a philosophy) I have a good handle on the fact that Catholicism, and in general Christianity, is not universally known or accepted. Although, about 25% of people on earth are either Catholic or Orthodox, and if we add in non-Catholic Christianity, it is about 33% of the earth ... spread around the globe. I have also studied the Koran, though I have not closely studied Islam. In some Islamic nations, Christianity is virtually unknown ... and not permitted to exist.
The problem in our discussion is how we use the term 'universal." To be 'universal' does not demand that a truth be 'known' or 'accepted' by anyone. A 'truth' can by completely unknown, and still be true, and be absolutely universal. I have no doubt that as humans move out into the universe more, we will discover many new truths ... new to us, that is, but timeless truths that have always existed.
At one time, all people on earth thought the earth was flat ... then they thought it was the center of the universe ... and now we know that earth is a tiny little planet on the outer 1/3 edge of one of the spiral arms of a medium size galaxy, with 100 billion stars; and it is merely one galaxy in an estimated billion or more galaxies. The truth of our existence and place in the universal was not known or accepted by anyone on earth at one time ... but the "truth" was nonetheless true and universal ... and at one time, as some begin to study and form speculation about the universe, it took "faith" using what they did know to 'believe' the universal truth of our existence ... a faith that is no longer needed today ... but the truth stands, and is good. Yet, there are still people on earth who do not know about the universe ... and the 'Flat Earth Society' still exists, and claims that the 'proofs' of a spherical earth to be a conspiratorial hoax.
Likewise, right now, what I accept as 'truth' in the person of Christ is not known by all, or accepted by those who do know. But, it can still be 'truth' and in fact 'universal' truth ... that is, God can be the same everywhere to everyone all the time. Jesus can be his only son, and our savior. Right now, however, I openly admit that this truth in my life, is a matter of faith. Time will prove whether it is a universal truth.
Existentialism is an enemy of religious truth. Not necessarily metaphysical truth, which cannot be quantified anyhow.
No, it is not. People with a certain agenda can become enemies of truth. However, existentialism is an outmoded approach to philosophy. This field is still evolving, and currently, philosophers have moved from finding grand theories to establishing mini-theories.
Morals and ethics can be tested. We know that to be honest and loving is a more healthier way of living then its opposites. Why that is so is another issue entirely.
There are time honored morals and ethics, and time-dependent morals and ethics, and situational ethics. Therefore, depending on when one lives, and where one lives, some things considered moral and ethical can be healthy or less than healthy.
Religion/theists/Christians claim that moral/ethics are their sole territory. This is a claim that is getting less credence by the evidence of atheists and agnostics being shown to have morals and ethics too.
No, they make no such claim ... this is a myth.
Again, personal truth is different from truth. And it is clear that personal truth = faith. Real truth has nothing to do with personal truth. It is important though that we each individually have our own personal truth. But you can't push that or promote that to anyone else.
Personal truth is not necessarily equal to faith. Personal truth may not involve any faith. Faith is an act that one engages in, for different reasons ... some have blind faith, some have faith based on trust and experience, other have faith as a gift. But truth is time honored, and independent of faith. Faith can move us toward truth ... but these two are in inextricably linked.