Spiritual truths are tied to spiritual practices.
People have discovered over thousands of years that if your mind behaves in a certain way, it will change in the desired way and if you fail to do so or let your mind behave in another way, the change will not give the desired freedom or expansion of spirit.
So spiritual truth is not something that can just be made up, but is more like in science, it follows from experiments that always point in the same direction.
This is the reason why the original teachings of Yeshua are not that much different from those of let's say Shiva or Krishna or Buddha.
The individual teachers may add some new aspects or elaborate in certain directions, but the truths do not contradict each other, but rather support one another.
That is why spirituality can be seen as a science of the introspective or intuitive mind.
This has nothing to do with so-called "religious truths" which are made up by religious folk.
I don't know why there are still educated people who support religious tuths rather than spiritual truths.
For me they are like people who believe in weird theories about aliens living in the brains of evil people in power, like people attracted to the irrational.