"Yoga is a group of Physical , Mental , and Spiritual practices or disciplines which originated in ancient India. Yoga is one of the six orthodox schools of Hindu philosophical traditions. There is a broad variety of Yoga schools, practices, and goals in Hinduism , Buddhism , and Jainism." - Wikipedia
Yoga's techniques have some short-term Physical benefits. However, if a person wants a more "complete" experience they also have to exercise the Spiritual aspects of the discipline. TM is one of those practices.
Everything that a person Needs for Life and Godliness is Found in Christ. 2 Peter 1:3
To Seek elsewhere for anything is to veer away from the Truth .
To veer away from the Truth is to invite Death. Deuteronomy 30:19
The enticement that is used for Yoga is that it relaxes You. Relaxation is another Word for Peace .
Christ is our Peace. Ephesians 2:14
Another argument is that Yoga is healthy.
Christ ( Word ) is our Health. Proverbs 4:20-22
Yet another argument is that Yoga enhances life.
Christ is our Life. John 14:6
Put away the strange gods
The encroachment of Paganism was a persistent theme in the Bible. It is still a serious Issue today.
Genesis 35:2 Joshua 24:14 Joshua 24:23 Judges 10:16 1 Samuel 7:3
If You Need Proof that Yoga is an empty practice look at India where it was Created. India is a Weak nation with a caste System that enalbes its people to cope with its societal problems.
Contrast the emptiness and self-absorption of Yoga with what Christ has given us:
John 10:10
The thief cometh Not , but for to Steal , and to Kill , and to Destroy : I am come that they might have Life , and that they might have it more abundantly .
What does the Abundant Life look like?
Galatians 5:22,23
22 But the Fruit of the Spirit is Love , Joy , Peace , Longsuffering , Gentleness , Goodness , Faith ,
23 Meekness , Temperance
Psalm 91:16
With long Life Will I satisfy him, and shew him my Salvation.
3 Jhn 1:2
Beloved, I wish above All things that thou mayest Prosper and be in Health , even as thy Soul prospereth.
We should pursue Fellowship with the HolySpirit in order for the Fullness of the Life of Christ to Manifest in us - Not some empty, Pagan wasteful practice like Yoga .
Don't get caught up in the Wrong thinking that Jeremiah Spoke of in this passage:
Jeremiah 2:13
For my people have committed two evils; they have forsaken me the Fountain of Living waters, and hewed them out cisterns, broken cisterns, that can hold no water.