Yoga is independent of any religion. There is no such thing as Christan Yoga, Buddhist Yoga, or like that.
It has hardly any relation with religion. It is like Science. Science is looking the truth in the material world. Whereas, Yoga is looking the truth in the body, mind and soul. Yoga is to keep yourself and the environment in harmony and happiness.
Yoga makes the mind body and soul flexible and prepare you for the eternal glorious life. Yoga makes you strong, firm and steadfast in every sense. Yoga makes this life and the life after as the place of Paradise.
Yoga is to increase your faith in your own religion.
Yoga is acknowledging the divine power of God within us.
If you are a Christan, Yoga will help you to increase your faith on Jesus.
It has nothing against Christianity.
Yoga increases, faith on your God, godliness, brotherly kindness; and love to every being.