Mainly, in the west, yoga is understood as either indian-themed calisthenics or meditation. As we shall see, neither of these are authentically indian, and both are intimately related to one another.
The former is a repackaging of the calisthentics of Pehr Henrick Ling, a Swede. This system is very powerful and beneficial to Israelites (Europeans), and was probably the basis of the Nazi system which created super-soliders that inspire great fear and awe, still today. So, after the war, it was effectively demolished in its Christian, European character with bastardized names and intentions, styled after voodoo/cabala gods of the indian subcontinent. For example, a certain pose is called the peacock pose, which then officially is the adoration of a three-headed monster. Meanwhile, the names and language imposed over this practice is so garbled and nonsensical that practically no one bothers to study it. The words seem silly and unpronouncable, and claims of being indian, india being very far away and inacceessible until recently, left wholely unchallenged. Thus "yoga" gymnastics lessons continue to be patronized mainly for their physical benefits, while their promotion is largely based on a commercial, exotic packaging with little or no basis in reality.The latter, on the other hand, is typically presented through meditation groups, self-help literature and new-age/hippie types. Anyone having trouble in life and doubts about Christianity is encouraged to find God through a series of often beneficial practices, which include loving animals, sitting in silence, focussing the mind, eating less meat, fasting, barefooting, massage, and stretching. Typically in these groups there is an indian or at least asian role model presented, and the group begins attempting to substitute the seeker's 1) vocabulary with "indian" or "sanskrit" words, 2) ideas, not from this "fake world", 3) objective perception with solipsism, 4) Christian, altruist morality with egoism and 5) obedience to familiar authority with that of a new, proposed role model.
So it's basically a commercial and spiritual exploitation of the weak. Although it's true that many of their practices are good for getting up on one's feet, their goal is to manipulate the interpretation of these results from "God inspired me to do better" to "effort-maxxing", i.e. a kind of gnostic, "I can be as God", or "I don't need God".
Speaking of gnosticism, if one views its principle characteristic as dualism, yoga is teaching this in full force. Yoga underlines not only the differences between the spirit and body, but starts to degrade or undermine the value of the body, with mottos like "I am not this body". Its techniques to chastity are basically a deconstruction of the physical object of desire into filthy, disgusting components (in chinese, bujingguan). It ultimately hates the material world and our material bodies, which means not having children, even practicing infanticide or killing the elderly. It posits that a demon rules the material world, or even that he created it (which is why many call Satan the Demiurge). To gnostics, reincarnation is possible because the body and the soul are very separate things, and although they believe in justice, they do not believe in a loving Creator who can forgive his repentant sons.
Many people do not know this (because pop Christianity is rife with gnosticism), but traditional theology teaches that we have a "body-soul" or a single, unified nature with two discernable aspects, the material and spiritual. Thus we could say that: as God is triune, we are "diune". We are taught that in extreme cases we may have to sacrifice the material "side of the coin", having faith that it will be regenerated later. If one side of a coin is marred, we can tell what kind of coin it is and re-engrave the other side. (There are even instances of brain injury victims regenerating their brains and recovering memories etc.) When we die, according to Catholic theology, our physical side is just temporarily marred and will be completely and more ideally regenerated with the "resurrection of the dead".
Because our God loves us, he can forgive us if we repent - as love includes a parent's desire to help his children grow. That forgiveness includes paying the price of our wrongdoings, something which the karmic machine could never do, i.e., according to asiatics, whatever you do to others will be done back to you, period. If we could really sit down and analyze all our wrongdoings, all of us would quickly realize that we cannot pay back our sins in this lifetime - not by a long shot.
So what of the influence of other souls? Well, Catholic theology is much more realistic and flexible than reincarnation. Realistic in that, we cannot go around claiming we are great people from the past, always with higher social status than ourselves as indians do, acting out of their retarded, arrogant nature. Flexible in that, living souls can influence any number of others, and it is not necessary even that their bodies be "dead" first. For example, I took a huge influence from a grandfather, looked just like him and had his mannerisms until I was eight years old, but he was living until I was three. His status as dead or alive had no effect on my body-soul's resonance with him. He resonated also with a couple other of my cousins, both before and after his death. Resonance happens when forms are similar, and families inherit and develop many older forms from within the family. The more similar your form, either internal or external, the more you will resonate with your parentage, from no matter what generation.
There is much speculation that stars are these ancestors chanting in heaven, and their voice when passing through water, transforms into twinkling light. The concepts of star and angel are used interchangeably in the Hebrew bible, and there are videos of experiments showing sound transformed into light through water online. Theology teaches us that each body-soul of our ancestry that went to heaven is still there, waiting on Christ's second return and the resurrection of the dead to have their bodies regenerated. So it makes perfect sense that they are all still there. And there is only six thousand years of human history, which means roughly two thousand generations - a large number, but not infinite, and justifiable from observation of the night sky.
With reincarnation, however, each soul is limited to one body. One also doesn't comprehend how bodies and souls would be separated, and why our current bodies match our souls so perfectly. In yoga, one is encouraged to wipe away one's identity, claiming that the spirit world has no bodies, no male nor female, no nationalities....yet if any of us were hard pressed to describe ourselves, we'd inevitably refer to these basic points as a start. So what would a soul be without a comprehensible identity?
I suspect it'd be fodder for the demonic realms, hell and 2nd heaven. They could feed on your energy, stripped of its material aspect (dead) and identity ("enlightened"). Demons would also like to use your material body dispossessed of its identity and possess it. So basically these esoteric doctrines and techniques they claim to take us beyond the material world, body and identity are a trick to turn us into demon food.
Thus the illogic of yoga is a very sneaky way to bring people to Satan. The Nakhash (snake) in the garden never asked Eve's obedience to or worship of Satan, but rather proposed a worship of the self which leads to cabala/satanism. Nihilism is never promoted outright, but one is encouraged to think "beyond" the firmament, to infinite space, time, and lifetimes. Rarely does it dawn on its victims that this infinity makes us precisely nothing. If one were birds, bears, princes, eskimos etc in the past, then what is one's identity now in comparison to all that? Which life is the "real" one? So, through the back door, yogis unwittingly give their lives over to demons and Satan.
Now very few have noted where we, White men, have come to have yoga in the west. Who brought it and why? One would expect to find demonic origins, and indeed we do: Madame Blavatsky, the ukranian joo whale, openly promoted satan worship in her magazine deftly entitled "Lucifer", and started a rumor that "someone changed the Bible" and deleted reincarnation doctrine out of it. Around 100 years later, jooz and freemasons, through the unitarian church etc. began citing and copying Blavatsky and her Theosophy, meanwhile promoting aristocratic, westernized poo people as great spiritual masters, the first major one being Vivekananda, then the most important one following him, Yogananda, the Kali (Satan) worshipper, sex fiend preaching chastity, the Nakhash teaching solipsism/self worship ("Self-Realization Foundation"), supplanting and subsuming Christ...and in sum, everything you'd expect from a turd world pajeet freak.
Another claimed source for reincarnation in Christianity is Origen (lit. "Son of Satan/Horus"). There are three main problems with this claim: 1) He is officially considered a heretic anyway 2) He claimed souls descended from Heaven into the womb, not reincarnation 3) He explicitly denied reincarnation in his vast body of works (over 2,000 books) [1].
Yogananda and any other poo simply have no clue about Catholic theology, biblical exegesis or Church history. Aside from the above cited theology of the body-soul, one could simply read in one's Bible Hebrews 9:27, John 1:21 and Matthew 17, for starters, showing: 1) we only get one chance at life 2) John denies he is literally Elijah and 3) Elijah actually shows up while Jesus is talking to John, etc etc. But don't expect honesty from granny scammers and shid eaters.