The concept of transcendence is a popular one, particularly if you've dabbled in Eastern philosophies. Though one aspect of most religions is to propagate a creator, flourish creation, the idea of transcendence is to move beyond all of that above the realm of matter. Hence, transcendence is typically associated with Shiva, the lord of destruction, or his yoginis/dakinis, the fierce destructive feminine often frowned upon by those who worship the creator.
1. Religion and Much of Spirituality is NOT Transcendence
Much of what we tout as "spirituality" or "religious", does not fall under the realm of transcendence. Again, most religions worship a creator, or manager of creation who leads us from the dualistic concept of unrighteousness to righteousness. Let's take religion for an example, where much of our scriptures both Biblical and Puranic or more political/historical based as opposed to understanding the realm of spirit.
The Biblical Old Testament, from my research, is merely expounding the Jewish politics of the "Holy Land", where much of the testament of these ancient Hebrews seem to be an attempt to show the political landscape of the Canaanites. In addition, much more is disclosed by the Akkadian, Sumerian, etc., script, that leave one questioning who this jealous Old Testament deity may have actually been. The same applies for the majority of Indo-Aryan Vedic-Puranic script, where these Aryan deities look a lot like Greco-Egyptian beings, much like the infusion that was brought under the Hellenic period. To tie into the "Holy Land", the controversial work of Zecharia Setchin holds that it was Sumerian Goddess Inanna held domain over the Indus Valley.
The Goddess Inanna holds numerous symbolism that may have some connection to other stories. Just as Inanna went into the underworld and had to raise herself up into the heavens again, so did Sati/Parvati in Hinduism have to use yoga to remember herself while she was lost in samsara (Spirit wandering in Matter). Moreover, just as Mary Magdalene was healed of her "seven demons" by Jesus, Inanna had to go through "seven" gates of hell. Lastly, the whole going into the underworld, and being raised from such "death" is akin to our seasons of winter and springtime where another name for Inanna is Ishtar, which some have claimed is the root of "Easter". Constantine was a well known devout pagan, and my research is showing more and more, that just as how the ancient Hebrews synthesized all other Canaanite deities into the Canaanite deity Yahweh, Constantine may have well synthesized the numerous Roman-Greco-Egyptian (Dionysus, Mithraic, etc.) cults into one deity, Jesus. Modern Christians say that such pagan influence was done mainly to convert the pagans, where it is well known that Jesus was not born anytime near Christmas (Mithraic Concept). An odd understanding, especially since the Roman Church is controlling what would otherwise be a natural cycle under the seasons and astrological patterns via the unnatural Gregorian Calendar. The Roman Church was capable of more than just blending with pagan myths, where one has to consider the Church's intent, especially since much of the Roman Church teachings drastically contradict the much earlier Gnostic Christian teachings.
Further, much of what is deemed "spirituality" also still falls under the material arena. Like religion which sought to control history, control government via tradition and culture, which is really supporting the realm of material creation, much of spirituality is quite similar. Mindfulness teachings, unlike Advaita, teach one to be present to the moment, to what is being observed. Such mindfulness makes one mindful of the material realm. Sure, such teachings have purpose, but it may only be slight transcendence where one is still focused on matter.
Moreover, we have these "mind, body, soul" teachings. However, the body is part of the material realm, and mind-thoughts are typically associated with the body being the receiver, interpreted by the receiver, and are therefore based on form or the material world. Hence, the mind and body are part of the material realm. Further, unlike religion, mystics separate Spirit from Soul, where soul is simply the aspect of one that moves from one body identity to the next via reincarnation, where Spirit is beyond creation. Soul would be the glue between Spirit and Matter, where most souls only look towards matter. While the soul maybe the watcher of the body and maybe external events, Spirit may be the watcher of the watcher of the body, or beyond where there is no form/tangible to watch. So these spiritual "mind, body, soul" teachings do not fit the venue of transcendence.
2. Transcendence is Dissolving the Jars We've Placed Ourselves In
In Hinduism, unlike the Vedas or Puranas that propagate a being to be appeased or worshiped, the mystics crafted the more subtle Upanisads, which was historically met with disdain as with every mystical tradition. There is the understanding of an Atma, or little spirit, and Brahman, which implies the ultimate truth. Such concepts are described with the metaphor of Atma being like the air inside of a jar, and Brahman being the air outside of a jar. These simple truth is again described in the Saiva mystical tradition as a meditative practice in the Vijnananbhairava. Here, to truly know thy self becomes key, to know the air within sans the jar, where all of our yogic-meditative practices is to dissolve the jar.
Again, our religions and spiritual concepts are full of ideas that simply add to the jar. We worship the one that created the jar as opposed to the essence behind it, we worship and place on pedestals those that have the nicest jar based on religious-moral-cultural standards, we fight over jars that are associated with different identities, we create and honor a lineage for the jar, some even worship and honor the elements that compose the jar, all the while the air remains unlimited and free from all such labels, humanity has tried its hardest to make the air form itself into a jar.
Many masters have come and pointed the way, but as Osho would say, many would rather cling to the pointing finger and even suck on it. Here, the jar becomes the finger, where many would rather worship the finger as opposed to truly understand the concept of, "the Kingdom of Heaven (God) is Within You". (Luke 17:21). In addition, the master himself states, "Do not let heaven's kingdom become a desert within you...I tell you the truth, whoever will receive life and believe in the kingdom will never leave it, not even if the Father wants to banish him". The Secret Book of James.
Going back to transcendence and the use of tantrik deities that are typically fierce and opponents to creation (matter), and the use of meditation to disassociate from all material and tangible so that one is no longer lost in the illusory world of form, all of these transcendental practices as taught by the Tantriks, Gnostics, Hermetics, Alchemists, Sufi's, etc., in violent contradiction with orthodox beliefs (Brahmanic- Hindu, Orthodox Christian, non-Akhenaten Egyptian, Modern Science, Islam; all designed to either worship or study the jar), are done in order to dissolve the jar. We are not the religious stories and cultural heritage; we are not the mind, body, soul; we are not the world of form and the elements that compose it. We are so much more, and yet, so much less.
To dissolve the decorated jar that we are so deeply attached for the air, is the meaning of transcendence.
To transcend is to move beyond matter and form to Know Thy Self, the True Self.
To know the True Self, the air, is to Realize who you have always been.
The air inside the jar is the same as the air outside of the jar.
Don't take my word for it. After all, who am I to say that I know anything.
When in fact, I know nothing.
No-thing. Not this, nor this. Neti Neti.
In an intentional approach to the mystical life, therefore, it is first necessary to rid our minds of all prepossessions and predispositions, of the opinions we have formed, the conclusions we have formed, the conclusions we have arrived at arbitrarily, and especially by way of hearsay. We must mentally disrobe, remove the cloak of custom which we unconsciously had wrapped about ourselves more firmly each year. We must free our minds of all such encumbrances and be prepared to accept only those things which, as the famous philosopher Descartes said, arouse within us an intuitive acceptance of them, feeling that they are true and constitute real knowledge.
Overly educated and continuously exploring and revealing more behind the veil.
"It cannot be too highly emphasized that the mystic swims in the same waters in which the psychotic drowns."
-James Wasserman, The Mystery Traditions