When staring in the face of adversity religious people will often invoke the name of their god. For example, a Buddhist would say "Buddha, Buddha!" whereas a Muslim would say "Allah, Allah!" These words strengthen them against their problems and invoke the omnipotent nature of their particular deity. In rural Cambodia, a lingering legacy of pre-Buddhist animism provides an important social structure. Pithi Sen - Prein is a traditional ceremony referring to all and any spirits. Of special importance are the ancestors and their active role within contemporary world of the living. "Me" is the female ancestor; while "Ba" is the male one and the phrase "Chah-Tomm" refers to the ancestors. For a rural Khmer invoking the power of the ancestors is the most important force they can call on.
For centuries rural Khmers have enacted this ceremony when any problems, such as ill health, befall their family members. The animism, that existed prior to the arrival of Buddhism, taught that all things have spirits. Inanimate and natural phenomena all have souls. An important part of this cosmology was the role the ancestors play. They had to be appeased, consulted and even worshipped in their own right.

A prime example of this is during a ceremony of a wedding. The Acha will always make offerings to the spirits of the ancestors. This is to let them know about the marriage and to ask for their blessing. Those who do not take this chance to placate the spirits are courting disaster. If a family member falls sick with strange symptoms like: exhaustion, anxiety, melancholy, insomnia or hysterical crying. If all the medicines do not work and there are regular periods of sickness, this is when, for whatever reason, you have angered the ancestors and a Me-ba is angry with you. According to Khmer tradition there exist four types of Me-ba:
Chah-Tomm Kramom-Kamloh or Me-Ba Kramom-Kamloh (Kramom is a young girl and Komloh is a young boy) is the Me-ba who gets angry only with young girls and young boys who fall in love each, and conceive a child outside of wedlock. This Me-ba gets angry only with the young girl's relatives.
Chah-Tomm Rolom Sner or Me-Ba Rolom Sner (Rolom is to fall down, Sner is to love) is the Me-ba who gets angry with young boys and young girls who fall in love with each other secretly. This Me-ba gets angry only with the young boy's relatives, especially the people living in his house.
Chah-Tomm Pkabb Mokk or Me-ba Pkabb Mokk (Pkabb Mokk means face on the ground) is the Me-ba who gets angry only with married men and married women who have clandestine sexual intercourse with each other.
Chah-Tomm Peak Somdei or Me-ba Peak Somdei (Peak Somdei is a word or speaking) is the Me-ba who gets angry with the families who have internal conflicts: if there is a breakdown of the family unit leading to dysfunctionality on all levels. The occurrence of anyone of these amoral actions incurs the mighty wrath of the ancestral spirits. This will be manifested as sickness, normally not afflicting the perpetrator of the offending actions. This reproach from beyond the grave is supposed to punish those who do not look after and take care of their families.
Once it is established that you are a victim of the wrath of a Me-ba, the next is to identify exactly which me-ba it is, in order to know how to placate it. Pithi Bol Porng Mornn (Bol is to predict or to pray for something, Porng Mornn is a hens egg) is believed to be the best way to find out which of the me-ba has been angered.

To begin the ceremony they take a tray and burn incense to summon their ancestors. They then call out the names of the family members whilst balancing the hens egg on the tray. If the egg stands when the name is called then that is the person who has committed the mistake. The expression for the anger of the me-ba is "karch" and implies the sickness resulting in the fury. A firm believer in this ancient ritual is Yeay Orn, a 67 year-old woman in Peaream commune, Bati district, Takeo province. She states that: "Me-ba karch is true and bol porng mornn is not a lying thing. . .because if any couple did not commit a mistake, the porng mornn cannot stand. In other words, we can say that this couple or that couple committed a mistake"

Yeay Orn extrapolates, highlighting some of the difficulties involved: "For the Me-Ba Kramom-Komloh, it is easy to find out the persons who cause the anger, because after we perform the egg ritual we compare this with the actual activities of both the boy and the girl. Then we can take them to sen prein easily. On the contrary, for the Me-Ba Pkabb Mokk, it is difficult to find out who caused the me-ba to be angry because they are both married." After they find out, which Me-Ba is causing the problem, they must prepare pithi sen prein: to apologize to the spirits to stop their anger with the younger generations. To help the spirits be patient in allowing the children to improve with time Pithi sen prein must be prepared near the patient, with seven or eight elders and the people who caused the problem present. Also lain out are: four plates of food, sweets, rice, five candles, five incense sticks and cigarettes, for the spirits.

After all the people come together as one, they start lighting incense whilst reciting incantations saying: "Today is a good day that we prepare things to offer the me-ba who is angry with us and causes the patient to become sick. Please accept our apologies for not looking after him or her (those who make the me-ba angry) but now they come and salute the me-ba to ask forgiveness for all of us and for the patient to get better and better." They say this three times and the person who caused the me-ba to be angry, also salutes to all elders who join this pithi. After this pithi the two who caused the problem become a new couple.
"Me-ba karch (angry) is logical, because once our son got a cold with a high temperature and all medicine was useless, so I decided to find someone to find out what happened. We then found out that the me-ba was angry with us because my niece had had an argument with me and we had not spoken for a long time. After sen prein, our son get better" said Mr. Pen To, a 38 year-old villager in Trapong Thea village, Tamng Yarb commune, Prei Kabars district, Takeo province. Although the pithi sen prein is different from place to place but the main concept is the same. The same aim of appeasing the ancestors is a unifying theme. This belief and its practice are still very much alive in Khmer society. It serves an important role in the education of morality. It serves as a righteous code of conduct; being faithful, not fighting and keeping within the expected norms of behavior. The power it holds is that where one can hide ones actions from a human, a Me-Ba sees all.