The evil eye, known as ματι, is known to have been a fixture in Greece dating back to at least the 6th century BC, when it commonly appeared on drinking vessels. In Greece, the evil eye is cast away through the process of xematiasma (ξεμάτιασμα), whereby the "healer" silently recites a secret prayer passed over from an older relative of the opposite sex, usually a grandparent. Such prayers are revealed only under specific circumstances, for according to superstition those who reveal them indiscriminately lose their ability to cast off the evil eye. There are several regional versions of the prayer in question, a common one being: "Holy Virgin, Our Lady, if so and so is suffering of the evil eye release him/her of it" repeated thrice. According to custom, if one is indeed afflicted with the evil eye, both victim and "healer" then start yawning profusely. The "healer" then performs the sign of the cross three times, and spits in the air three times.
Another "test" used to check if the evil eye was cast is that of the oil: under normal conditions, olive oil floats in water, as it is lighter than water. The test of the oil is performed by placing one drop of olive oil in a glass of water, typically holy water. If the drop floats, the test concludes there is no evil eye involved.
If the drop sinks, then it is asserted that the evil eye is cast indeed. An alternate form of the test is to place two drops of olive oil into a glass of water. If the drops remain separated, the test concludes there is no evil eye, but if they merge, there is. This is usually performed by an old lady,who is known for her healing, or a grandparent.
The Greek Fathers accepted the traditional belief in the evil eye but attributed it to the Devil and envy. In Greek theology the evil eye or vaskania (βασκανία) is considered harmful for the one whose envy inflicts it on others as well as for the sufferer. The Greek Church has an ancient prayer against vaskania from the Mega Hieron Syenekdymon book of prayers (Μέγαν Ιερόν Συνέκδημον).
http://en.wikipedia.org/wiki/Evil_eye#Greece
