NannyC2 Yoga is not about religion, it is entwined with Buddhism which teaches the same philosophy as in the Christian faith, which is to be a good kind person, to think of others before yourself, to non-harm including animals and so on. They do not worship a God.
Yoga teaches that you need to start with a healthy body and that in turn will lead to a healthy mind.
As others have said NTO you are in the wrong class, find another that suits you. I do gentle yoga and a more dynamic yoga, but my students follow me to each class as they know that even in my more dynamic classes, I above all emphasize reading your body, leaving out anything not for you and of course I know my regular students well, so know their limitation and would tell them not to do this asana then give them an alternative or give them a variation of an asana [posture] that they can do more easily.
I have made very good friends with my yoga students, some have been with me for more than 15yrs. We have meals together, socialise together, holidays together and they always get an invite to any party I may have at home and vice versa.