Yoga is basically a Hindu religious practice. But is there anything actually spiritual involved? It seems more physical than anything else.
Hard to close shakra center or Edgar Cayce's third eye or pineal? gland) again if at all and for unclean souls an entry point for deceptive spirits. Just my opinion. Christian traditional posture can be postrate facing ground or kneeling. Kneeling may come from the bible, Every knee shall bow and tongue confess that Jesus is Lord. Also standing. Not sure about biblical traditional postures, lots of paintings notwithstanding.
In the bible, when a posture is mentioned, most seem to fall forward (or just fall) when experiencing an overpowering spiritual experience.
Many charismatics seem to prefer turning palms upward. I don't know if it matters too much except at masses if your heart is right with God.
**But is there anything actually spiritual involved? **
Very contemplative.
I will worship God and not a Hindu god.