One from oldest teaching (with material proof 3000 BC) - Old Yoga or Shivayoga - today open for all people.
This is best, simplest and easiest way for continue with develop each psychic life. This is way involved in all religion, mystically, scientifically,.. teachings.
Soul through God became "One with God" in realized levels of fullness conciousness. (Not other ways!!!)
Soul's life without separation of God is soul's goal.
Haven't separation between soul and God for realized soul.
Soul only through many levels of fullness conciousness start live with God on many levels deeper and deeper.
Divine concentration or Shivayoga or meditation or prayer or yoga is way to God and God's doing.
God first show soul what must do, God must first give own meditation on Self each soul separately (or haven't group doing/initiation) and teach each soul of this Divine way of comeback to own nature or to Our Source.