"But as it is written, eye hath not see, nor ear heard, neither have entered into the heart of man, the things which God hath prepared for them that love Him. But God hath revealed them unto us by His Spirit: for the Spirit searcheth all things, yea, the deep things of God. For what man knoweth the things of a man , save (except) the spirit of man which is in him? Even so the things of God knoweth no man, but the Spirit of God. Now we have received, not the spirit of the world, but the spirit which is of God; that we might know the things that are freely given to us of God." 1 Corinthians 2:9-12
There is a knowledge of God, a wisdom that comes from having the Holy Spirit reside in our life. The scriptures make it clear that those who deny Christ do not get internal revelation from God, i. e., understanding when reading the word of God and confirmation in their spirit that what they have read or heard from God is from God and not from man or from other spiritual sources.
It's not talked about much, but those who practice other world religions practice them using the spirit of man within them to discern spiritual things. They have valid spiritual experiences, but their understanding is not enhanced by the power of the indwelling Holy Spirit. Many of the things they believe are real, but they are not sanctioned by Holy God. There is no consistency among the world religions because there is no direction and agreement from the Holy Spirit to all those who practice religious experiences without the aid of the guiding of the Holy Spirit.
The Holy Spirit does not cross over and enter into the spirit of man just because that person is following or believing or practicing a religious philosophy incongruent with the Word of God. The Holy Spirit and the enlightenment that comes with having a relationship with God only comes by invitation from mankind to God to come in and make their spirit whole. Without this invitation, all of the spiritual experiences and practices are man made and/or other spirit made, meaning it may be spiritual but it is spiritual in the sense of being generated from mans own conscience, a fallen angel/demon or satan himself. These other experiences are why there is so much confusion. When a person creates their own religion without the guidance of the indwelling Holy Spirit, anything goes.
Other spirits will try to emulate the true Christian experience, creating a false sense of security that simply because someone had a spiritual experience that it must be from God. That's the goal of the evil spirits, to take people on a journey that never connects with Holy God.
"But the natural man receiveth not the things of the Spirit of God: for they are foolishness unto him: neither can he know them, because they are spiritually discerned." 1 Corinthians 2:14
Much of the world is caught up in religion without the Spirit of God. I don't fight them. I love them. But I don't try to act like, since they have a religious philosophy, that somehow that means that they are worshipping the same god. No they don't worship the same god as we do and no they don't believe like someone who has the indwelling Holy Spirit, and no they don't receive the same messages from God that we do and no they aren't going to pass into the everlasting with understanding. Those who understand on this side will understand on the other side. Those who don't understand on this side aren't going to understand on the other side either. Rev. 20:15