Everyone is capable of feeling the spirit, but only worthy Mormons get to have it with them all the time. For example, an investigator can feel the spirit just enough to know the Book of Mormon is true. The built-in innate human nature to do good to other people is considered the light of Christ and it is in all people. But again, only Mormons can have the spirit with them 24/7.
When you are sharing the gospel, the spirit will put words into your mouth and you will be able to easily convince everyone to join the church. This is considered especially true of missionaries. When you share the gospel and that person doesn't join, it was because their heart was hard and they could not feel the spirit.
Each person in the church, in good standing, is entitled to personal revelation via the spirit. If you have a problem or dilemma in your life, the spirit can help you make correct decisions. If you make a decision based upon the spirit, and it turns out to be wrong, it is justified by stating things like, "god had a lesson for me to learn" and other such nonsense.
The spirit is described as a "still small voice" in Mormonism. Because god is a man with an actual physial body, he cannot personally give you revelation. That is what the spirit is for. The spirit or holy ghost is a third member of the godhead and he is an actual man in spirit form. The spirit is able to penetrate into your heart and give you inspiration.
You can only "hear" it if you are very in tune with it, much like tuning an analog radio to a specific frequency. In fact, Mormons use the radio analogy to explain how the spirit works... it broadcasts a signal and everyone who is tuned in can benefit from it. Because it is not easy to hear, one must be very in tune and listen for promptings (feelings). If you haven't noticed by now, Mormons put a huge emphasis on feelings.
I know a girl who is separated from her husband and is very much out of love with him. She is Mormon and has told her husband that she has been praying about what to do and the spirit is nagging her to get a divorce. (Never mind the fact that she has been extremely sexually immoral and that negates her ability to receive revelation, but I digress).
The part that I find amusing is that her husband, in reply to her claims of revelation for a divorce, has claimed that in answer to his prayers, they are supposed to stay together and work things out (never mind the fact that he is a convicted sexual predator, having been familiar with young girls in his own family, therefore he is also unworthy to receive revelation).
On a slight side note, this is how Mormonism works. If you're "unworthy" to be guided by the spirit, you just pretend that you are since no one will really know the difference. By Mormon standards, neither of these two people are worthy to receive revelation and yet both of them are claiming that they do. I have talked about this before... how in order to be a Mormon, you have to lie and pretend. You have to go along with the show because everyone else is.
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It is not unlike the story of the emperors new clothes where only the "wise" can see the invisible clothes. No one really can see them (because they're not there) but no one wants to admit that they can't (and therefore aren't wise) and so they all pretend. Since everyone is pretending, all claiming to be wise, everyone single one of them is an arrogant fool who is too afraid to just admit the truth because they think that they would be the only one who is a fool. So they are all just happier to keep lying to each other. Mormonism works on this very same principle. They all claim to have the spirit and receive revelation because everyone around them does too and they don't want to be the only one who can't seem to get with the program. So in the secret life of a Mormon, they all wonder what is wrong with them while everyone around them seems to be so with it. They beat themselves up inside and just play along. The truth is that they are all playing along and pretending, while secretly thinking that they are the only one who the system doesn't work for. It's the honest ones, like me, who finally get fed up and scream out, "This is all bullshit!!!!!"
Now, getting back on subject, why would the spirit give two unworthy people different answers to the same question?
Um, maybe because the idea of the spirit is complete and total bullshit?
Isn't it funny how the "spirit" always reveals to you the very thing that you personally want/think is best? And they claim it's not emotion! ROTFLMAO!
Mormons make poor decisions just like everyone else. When a Mormon makes a poor decision, it was a correct prompting but god wanted them to have a trial. When a non-Mormon makes a poor decision, it is because they couldn't feel the promptings of the spirit. When an ex-Mormon makes a poor decision, it's because they left the church and are now wandering around lost and confused.
Whenever a Mormon makes a right decision, he can't wait until Fast Sunday to get up and brag about how righteous he is because he felt the spirit and followed its promptings. Then they all cry together because the church is so true and the spirit is so wonderful.
And that's the spirit... No matter what it prompts, it was the right decision and the church is true!