Whenever there is an increase in spiritual manifestations, there is always an increase in both true and false spiritual phenomena. You do not get one without the other.
In Kirtland, new converts who were overzealous to participate in the new heavenly manifestations coming as a result of Joseph Smith's claims, opened themselves up to receiving influences they could not understand, and did not test for truthfulness. They were so delighted to have any kind of experience, they trusted anything "spiritual" was from God. As a result, there were many undignified things, degrading conduct, foolish behavior and evil influences which crept in among the saints. Joseph received a revelation in May 1831 concerning this troubling development. In it the Lord cautioned there were "many false spirits deceiving the world." (D&C 50: 2.) That Satan wanted to overthrow what the Lord was doing. (D&C 50: 3.) The presence of hypocrites and of people harboring secret sins and abominations caused false claims to be accepted. (D&C 50: 4, 6-7.) It is required for all people to proceed in truth and in righteousness (D&C 50: 9) if they are going to avoid deception. Meaning that unrepentant and unforgiven men will not be able to distinguish between a true and a false spirit.
All spiritual gifts, including distinguishing between true and false spirits, requires the Holy Ghost, given through obedience to the truth, which allows a person to distinguish between truth and error. (D&C 50: 17-23.) The truth is like light, and when you follow the light of truth it grows inside you until you have a "perfect day" in which there is no more darkness,but everything is illuminated by the light of the spirit within you. (D&C 50: 24.)
The revelation clarifies that a preacher of truth will become only a servant. He will not claim greatness, but will seek only to give truth; as a result of which false spirits will be subject to him. (D&C 50: 26-27.) But this only comes as a result of repenting of all sin, because the light of a perfect day cannot arise when men harbor evil desires and inappropriate ambitions within their hearts. (D&C 50: 28-29.) Truth will not leave you confused, but will enlighten your understanding. (D&C 50: 31.)
From this you can see how necessary it is for each of us to continually repent, conduct our lives in conformity with such truth as you presently understand, and avoid deliberate wrongdoing in order to be able to distinguish between a true and a false spirit. You must attract light. It is attracted by obedience to such light as you already have. When you proceed forward using the light you already possess to attract more light it will grow in one, consistent and truthful manner from a lesser to a greater light. All of it conforming to the teachings of Jesus Christ.
Ambition in spiritual gifts leads to acceptance of evil influences. As part of the same problem in Kirtland, in September of the previous year, Hiram Page wanted to be like Joseph, and was able to attract a deceiving spirit to communicate with him through a seer stone. But the commandments he received were designed to lead him into error. (D&C 28: 11.)
Truth will always testify of Christ and lead to repentance. It will lead you to do good, not evil. To serve God and not follow men. To repent and forsake darkness which appeals to the carnal mind. (See Moroni 7: 12-19.)
Just because you have a "spiritual experience" you cannot trust it will invariably be from God. True spirits will:
-Testify of Christ.
-Lead to repentance.
-Be consistent with existing scripture.
-Lead you to be submissive to authority in the church.
-Edify and enlighten your mind.
-Be understandable and not cause confusion.
-Cause light to grow within you.
-Turn you toward Christ, not men.
-Never cause pride.
-Make you a better servant.
-Increase your love of your fellow man.
-Clothe you with charity for the failings of others.
-Conform to the true whisperings of the Holy Ghost you previously have received.
-Leave you humble and grateful for God's condescension.
-Make you want to bring others to the light.
-Be grounded in love toward God and all mankind.
-Lead you to rejoice.
False spirits will:
-Deny Christ.
-Cause pride.
-Make you believe you are better because of the experience.
-Contradict the scriptures.
-Appeal to carnality and self-indulgence.
-Lead to rebellion against the church's right to administer ordinances.
-Cause confusion.
-Lead to ambition to control others.
-Make you intolerant of others' failings.
-Seek self fulfillment rather than service.
-Appeal to your vanity and assure you that you are a great person.
-Bring darkness.
-Repulse the Holy Ghost.
-Prevent you from repenting and forsaking sins.
-Interfere with serving others.
-Focus on yourself rather than the needs of others.
Do not think all spiritual experiences can be trusted. There is no difference between the activities of deceiving spirits today and those in Kirtland, as well as those in the New Testament times. If you follow the Lord you must still test the spirits and only follow those which point to Christ. (1 John 4: 1.) Even Joseph Smith had to ask God about some of the phenomena going on in Kirtland before he knew which were of God and which were deceiving.