That and prayer.

The modern idea of manifestation is that we possess some hidden power whereby speaking our desires can make them come true, but there is an ancient and well-established theological understanding of this phenomenon that is shared by Christians and pagans alike. Manifesting is an implicit call upon the demonic for assistance. If your manifestation comes true, it is because a demon used their powers to assist you, not because you have some power of your own. I caution everyone against this, because it is not to your benefit, but rather it is a glamorous snare. Opening yourself to the demonic is not an easy door to close, and it can ruin your life. Nobody believes this until they need an exorcist, and exorcists are in terribly short supply these days because of record-breaking cases of demonic oppression and possession.

If this sounds crazy, remember I'm not the one speaking my desires to the universe in an empty room 😂

One may think that prayer to God is a form of manifesting. But when I pray, it is for God's will to be done, not my own. Manifesting is to enact one's own will. They are actually opposites. Kind of like good and evil.

Sorry if that was a lot, but I'm just trying to speak the truth over here. This is a perspective a lot of people aren't aware of.