I find comfort, guidance, inspiration, and truth in all the religions I’ve studied; Catholicism, Islam, Judaism, Hinduism, Jainism, Wicca, etc.
From a Catholic perspective, it’s not proper to “mix” religions, but if one is not concerned with strict Catholic religious adherence, as I once was (and currently am, although I am trying to learn more and perhaps become a better Catholic), then nothing would hold them back. I respect everyone’s beliefs even if they mix and match. Some people feel that all religions are flawed, therefore following one completely is less sensical than taking bits and pieces of each and forming your own unique path.
My struggle now is trying to break away from this view and be a strict Catholic but it’s a process and I can’t change overnight.
Syncretism was one of the earliest heresies condemned by the Church. It might be helpful for you to look into the history.
What people feel, or some people feel does not change what is. Aristotle said, what is, is. What we think about reality does not change reality. We can either know reality for what it is, the truth about it, or we do not know it.
Logic says either all religions are false or one is true. All religions can have some elements of truth, but since they all disagree with one another, have doctrinal contradictions, then all either have some false belief or there is one whose doctrines are all true.
If all have some false doctrine and one tries to follow more than one it becomes up to the individual to try to figure out for himself which doctrines are true and false in each religion. You end up following no religion and making up your own.
In salvation history God reveals truth to mankind in general. He does not lead each individual into the individual’s own personal truth. If He did all people would agree on what they believe about spiritual truths. He would not tell one person one thing and another the opposite, or He would be deceiving. God can not deceive or be deceived. He is truth.
There is only one objective reality. Either heaven and hell exists or they do not. Jesus is the Son of God who came to save us, or He is not. What people feel, or more properly, think, about it does not change what is. He can not be the Son of God in reality for one person and is not who He is if some person or persons feel He is not.
You can know religious truth or you do not know it. If you try to find all truth, or the fullness of truth and belong to different religions at the same time you do not know truth. Jesus said He is the truth, the way and the life.
Different religions contradict one another. If you try to follow them all you end up confused and lost.
You either believe Jesus or you do not. He said He is the good shepherd. His sheep know His voice and will not follow a stranger, Buddha, Confusius, Krishna, Mohamed, or others. He said all who came before Him were thieves and robbers. He said you are for me or against me. There is no in the middle. If you try to follow multiple religions you will go astray, if Jesus is who He said He is.