Knowing so little about yoga, I am particularly unsuited to try to answer this question. But I had a friendly debate about it with a lapsed Catholic friend (and yoga enthusiast) earlier this week, and today’s Wall Street Journal has a fascinating column on the topic. And I’m a law professor, after all, so I won’t let a dearth of knowledge stop me from expressing an opinion.
My impression is that traditional yoga is based on a spiritual framework that has some similarities to aspects of Christianity but is quite inconsistent with it. The Bible teaches that God created the world and is distinct from it, which seems at odds with the eastern spirituality on which yoga as based. And, at least as practiced by many in the U.S., yoga seems to invite an odd combination of preoccupation with self, on the one hand, and complete emptying of self, on the other. Both seem inconsistent with our being subordinate to but made in the image of God, as the Bible teaches.
This doesn’t necessarily mean that yoga-like practices are always un-Christian, in my view, any more than mysticism is. But it does raise serious red flags, and suggests that while some of the insights of yoga may be useful, yoga itself is a spiritual distortion that is more likely to lead practitioners away from than toward the God of the Bible.