In Webster's Dictionary resonance is defined as: "The vibration of large amplitude in a mechanical or electrical system, caused by a relatively small periodic stimulus of the same or nearly the same period as the system's natural period of vibration."
Simply put: resonance is vibration, specifically a similar vibration.
In homeopathy this resonance refers to the affinity of one note to another, similar note - as with a piano. When a piano is played, all pianos nearby resonate to the same note. The term "resonance" nicely explains the principle of homeopathy. The vibration of a remedy moves on a particular "note" and the person who vibrates on the same "note" responds to it. To return to the musical comparison: homeopathy understands illness as a mistuning. The organism is out of tune and the remedy brings it back into balance.
To better understand this principle, it is important to know that homeopathy does not treat symptoms, but the person as a whole. The aim of a homeopathic treatment is to restore a person's health, in other words to bring them back "into harmony".
Homeopathy deals with the whole person: body, mind and soul. In homeopathy all aspects are taken into account.
Homeopathy also does not treat pain, since pain is merely a form of expression. On the other hand, one cannot say that homeopathy DOES NOT treat pain. An example:
There is an old story about a man who is just driving down the road when the oil warning light on the car's dashboard comes on. He pulls a shotgun from under the seat and shoots the light out (and of course half the dashboard). The man is satisfied because the light no longer annoys him. We all know the story is not over at that point. We know that the oil level is still low even though the light no longer shines. We also know that the engine will eventually overheat without oil and then stop working. It's the same with our body.
We can remove the signs or symptoms of an illness, but that does not mean they are cured. We can numb our pain receptors, but the pain itself and its causes are still there. If we do not treat an illness, it remains active until our body eventually gives out and stops functioning. For that reason, healing is always better than mere suppression.
Pain is usually a sign that something is wrong. In such a case it is better to pull the car over and check what is going on. Pain can indicate that something is not functioning correctly in a particular part of the body. Or it may be referred pain, phantom pain or psychosomatic pain. For simplicity, let us assume that a large proportion of pain is triggered by a dysfunction in one of our organ systems.
Pain is a signal of a disorder and we should not follow the example of the man with the shotgun. We must not destroy the early warning system but should follow that signal and find the cause.
Often pain first makes itself known with a faint whisper. If we ignore or suppress the cause, the whisper will eventually become a scream. Why is that? Our body does its best to function well and smoothly. If there is a disturbance, it must inform us and pain is often the first alarm signal. The worse the malfunction becomes, the more intense the pain.
The pain itself is not the problem, although it makes you feel unwell. The pain is only a symptom and not the disease itself. We can only heal if we address the cause and not just the symptoms.
------------------------------------------------------------------------------------------------------------------------------
Source: http://www.interhomeopathy.org/resonance_and_pain