In our study of the Spiritist Doctrine, we learn about the coexistence of the material and Spiritual worlds and the ways in which they influence one another.  If you have read (in our section on the scientific aspect of the Doctrine) about the Cosmic Principle and derivative fluids (or "energies") that surround us, you learned about how the thoughts of both incarnate and discarnate Spirits affect the vibrational environment of both worlds by imprinting their qualities on the spiritual fluids common to both realms, especially when considering the spiritual realms closest to Earth.  

In addition to effecting one another by influencing the whole environment in general, Spirits can- again through the will of their thought- exert direct influence on one another in much the same way.  An excerpt from Kardec ("The Gospel"* ch. 27, item 10) explains how this works: "We should first consider that all beings, in both the physical and spiritual realms are immersed in the Cosmic Principle that occupies space, just as we on Earth are enveloped by the atmosphere.  The Cosmic Principle reacts to impulses of will, and thoughts travel through it as sounds travel through air.  The chief difference is that, while sound vibrations are limited in reach, those of thought travel infinite distances in the Cosmic Principle.  When a thought is directed at someone on Earth or in the Spirit world- from an incarnate to a discarnate being, or vice-versa- a current of energy is established between them that transfers the thought from one to the other, just as air transmits sound waves.  The power of the current is relative to the strength of the thought and desire.  This is how Spirits, no matter where they are, hear the prayers directed to them.  It's how Spirits communicate with each other, and how they send their inspirations to us.  Finally, it's how incarnates can potentially establish (telepathic) contact with each other even at a distance."

Looking at this kind of Spiritual influence via thought transfer, we will focus here on the influence of the discarnate Spirits on human beings.  Question #459 of "The Spirits' Book" asks, "Do Spirits influence our thoughts and actions?", to which the Spirits answer, "To a greater extent than you suppose, they can have a significant influence on both."

The truth is that Spirits of differing moral and intellectual qualities are all around us, attempting to persuade us through the influence of thought explained above. What allows us to pick up on those thoughts directed toward us is our affinity with the Spirit that has directed them, or in other words, the level of attunement between the moral nature of our thoughts, desires, attitudes, tendencies, behaviors, etc. with those of the Spirit.   Think of it like setting a frequency on a radio in order to hear a certain kind of music or program.  The kinds of thoughts and actions that we cultivate set our mind to a given vibrational frequency, whereby we will "tune in" to the Spirits that are on the same frequency as our own, due to a similarity in nature.   Not only does our own nature open this door, if you will, to like-minded beings; it also attracts them.   Though most of us can not see the Spirits, they can (when interested) see us; but more than that, their heightened senses (in their freedom from the material body) allows them to see our thoughts and desires or intentions, whereby they will be drawn to us and recognize the increased probability of receptivity.  

The quality of the Spirits themselves determines how they look upon us as well as their objectives should they attempt to communicate with us.  Good Spirits empathize with those who are good or who want to improve.  They offer good advice, warn us of potential dangers, console us in our afflictions, rejoice with us in our successes, and encourage us to have strength and perseverance as we undergo our trials.   Good Spirits also seek to advance, through the influence of key individuals, the moral and intellectual progress of humanity as a whole; hence, the great scientific discoveries, peace efforts, etc. that we attribute to men and women on Earth most often originate from inspirations given to those individuals by collaborators in the Spiritual realm. 

In addition to the good and friendly Spirits that help us out here and there, each of us as one specific Spirit, sometimes referred to as our Spirit mentor or guide, guardian angel, etc., who is of a higher degree than our own and who accompanies us from birth to death. This Spirit helps us to make wise decisions, warns us of potential dangers, and offers us consolation as well as uplifting energies-- all through the work of intuition, ie mental suggestions that we chose whether or not to follow through our own conscience and discernment. (You can read more about Spirit Guides in "The Spirits' Book", Ch. XIII- Spiritual Intervention).

Just as we benefit from the positive influence of friendly and good-willed Spirits, we are also susceptible to unhealthy influences. When we "open the door of influence", through our own thoughts and actions, we are also susceptible to a Spiritual influence of a negative nature.  In some cases, this may come from frivolous Spirits, those who simply enjoy playing with us, causing us little annoyances and then laughing at our gullibility, impatience, etc.   In more serious cases, we may, through our own tendencies or areas of weakness- for example hot temperedness, egotism and/or self-centeredness, gossip, criticism or judgment of others, pessimism, participation in self destructive behaviors like alcohol abuse or drug usage, etc.- attract Spirits who share in our behavioral tendencies and who take pleasure in exciting such behaviors in us, encouraging us and egging us on at the first sign of temptation.  Other ill-intentioned or unenlightened Spirits may seek to bring us suffering out through their harmful influence, of anger or jealousy. The Spirit who  provokes negative thoughts and actions in a human being may do so with no fixed motive or may simply chose the person because they serve as a means to satisfy a general malice. In other cases, their intentions stem from a more deep-rooted hostility, as in the case with the Spirit who follows and harasses one who is an enemy from a previous incarnation.    

The frequent influences and suggestions that we receive from the Spirits around us and, in particular, those who we attract via vibrational affinity, are most often picked up as subtle intuitions in such a way that that they appear to be our own thoughts or ideas.  In this way, the suggestions do not interfere with our free-will; they may come from external sources, but only we can make the final decision, using our conscience and our knowledge to chose the actions we will take.  God allows the inferior Spirits to tempt us for they serve as the instruments through which our faith and constancy in doing good are tested; when we do not listen to negative suggestions and we overcome our temptations, we advance in our path of Spiritual progression.  Likewise, when we listen to the suggestions of good Spirits and chose wisely, the merit is ours for doing so by using our own free will.   To the contrary, when we do not follow their good advise, and when we listen to suggestions that lead us to opposite actions, the consequences we may suffer are only the effect of the cause that we created. To protect ourselves from the influence of inferior, uneducated, or suffering Spirits, we must keep our thoughts elevated as much as possible, working to keep from letting our guard down during those trying moments, and seeking to live, always, with compassion, faith, and determination.