Well, it is true that Asian Christians do practice forms of Yoga and Zen meditation based on Christian faith (in Japan, they even have “Zen Christian” temples). Thomas Merton practiced Eastern meditation in the lotus position etc. There is the Syriac/Indian Catholic monastery “Kurisumala Ashram” (Vagamon, 685 503 Kerala, India).
I wouldn’t have any reservation about doing Yoga or Zen within a Christian context. But I have taken a course in Yoga and wanted to share my experience with it - without generalizing.
I found the Yoga exercises to be challenging, but also healthful. They relaxed me and actually did put me in the “mood” for meditation and prayer.
However, I didn’t like the subtle and not-so-subtle teachings on Hinduism that I and others were being subjected to throughout the time we were struggling to hold a pose (and the Yoga was offered through a parish church and was held in the parish basement . . .).
When the Yoga instructor (a very pious Hindu/Buddhist apparently intent on making converts) began to relate the story of his friend, a former Catholic priest who became a Buddhist and a seller of all things Hindu/Buddhist, I had to step back.
He would go on about how his mother cried at the former priest’s funeral that her son had left the Church and his vocation etc. His attitude was an unabashedly triumphalist one - the woman’s son had “found the true way” and “get used to the idea.”
He and I would “talk shop” at times and when he discussed the Buddhist prayer beads, I would tell him about the Jesus Prayer and the Hail Mary Rosary (which he was aware of anyway). After a while, whenever he mentioned a Hindu/Buddhist practice, he would (for my benefit, it seemed) include a Christian/Catholic practice that resonated with it, just to show he was “ecumenical”

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I was just uncomfortable with what were perceived jabs at Christianity so I left.
In no way is this a criticism of the practices followed by Asian Christians of all denominations in their effort to inculturate the Christian message in that milieu, in response to our Lord’s command to “teach all nations . . .”
As an aside, I once saw a large cross in a (Japanese) friend’s home with an image of the Buddha on it.
In the 19th century, when Christianity was banned from Japan, Japanese police, in their efforts to smoke out remaining Christians, took crosses and placed them on the ground. They then made suspected Christians spit on it in hopes that those who refused to would reveal themselves as Christians and would then be put to death.
Christians however began to place images of a Buddha on their crosses so as to remove this weapon from the hands of the police. The Buddha represented the “Enlightened One” and in that instance it represented also the “Enlightener” Who is Christ.
Christians in Asia will represent Christ as a Sage and sitting in the lotus position.
FYI, in Orthodox Christian Georgia, an entire area of 100,000+ men, women and children were beheaded and tossed into the nearby river as they walked passed two Icons of Christ and the Mother of God while being ordered to spit at them. None of them would do it, so all of them died (they are commemorated as Martyrs in the Georgian Orthodox Church and so should be by all Christians).
This practice was also followed in the time of the Catholic Templars. A group of 80 Templars taken prisoner after the Battle of Hatteen were marched before a Cross with orders to spit at it. None of them did and all of them were beheaded - true Martyrs as well. When the time comes and the (true) Templar legacy is reconciled with the Church, perhaps these Templar Martyrs may find their way to the honours of the altar as well.
Alex