Religion

For non-Christian upland Gaddang, Nanolay is both creator of all things and a culture hero. In the latter role, he is a beneficent deity. Other gods in the Gaddang pantheon include Dasal, to whom the epic warriors Biwag and Malana prayed for strength and courage before going off to their final battle. The fathers of the two heroes were Bunag, the god of the earth, and Limat, the god of the sea.
Ilosa, the Gaddang universe, is composed of dufafa (earth) and kalekay (afterworld). In Gaddang cosmogony, the term denotes a place where all living things originated, the place where Nanolay performed his acts of creation. Dufafa is a world where famine, sickness, death, and uncertainty reign, while the concept of kalekay remains vague to many Gaddang. Even knowledgeable Gaddang mediums say that kalekay is simply the place of Nanolay, Ofag, and kararawa (soul). Nanolay is described in myth as a fully benevolent deity, never inflicting pain or punishment on the Gaddang. He is responsible for the origin anddevelopment of the world. Ofag is Nanolay's cousin, but does not have latter's creative powers. Kararawa are the souls of dead creatures, human or nonhuman. Upon death, the souls of all creatures go up to the kalekay, except cats, which are reborn ants, and chickens, which are reincarnated into butterflies. In kalekay, the kararawa go about living as they lived on earth. The absence of a "desirable destination" afterdeath for the Gaddang suggests an orientation toward the world of here and now. 
To the Gaddang, the dufafa is composed of "man, domesticated plants, ghouls, sickness and-amin (all)." Wallace (1970:87) observes that the Gaddang have a paranoidal fear of danger brought about by a history of headhunting and a present ridden with disease and malnutrition.
The Gaddang believe in two kinds of illness: the sickness caused by evil spirits, and the hurt or injury suffered in accidents such as those caused by falling, muscle sprains, and insect bites. The Gaddang also specifically identify blindness, insanity, birth defects, skin diseases, goiter, deafness, and malaria as other illness outside the first two classifications. Most "hurts" are attributed to natural causes, i.e., it is "natural" for an insect to bite or for a person to accidentally cut his/her leg with knife.
However, illness could also be caused by evil spirits, like the bingil, physically distorted humanlike ghouls with very large eyes that reflect light and glow in the dark, contact with which causes illness and even death in two days; aran, a mist like spirit, floating in the forest, which sneaks into the village at night and possesses a sleeping person, who will then begin to act insanely and die sooner or later; angakokang, known only by its distinctive sound like that of a whining dog, which when heard by a person will result in sickness  or death; aled, Tran substantial spirits normally invisible, but which have the power to metamorphose themselves into human, animal (pig, bird) and non human shapes (rocks, trees), and whose touch causes dizziness and general weakness, and death within a few days; and karangat, ghouls who like the aled, can change shape at will, are unusually aggressive and tricky, lurk about villages bringing sickness, insanity, and death, and must occasionally kill to secure their food, consisting of human corpses.
With evil spirits roaming around, the Gaddang become cautious about the world in which they live.  The earth world is an uncertain world.  Omens, taboos, and malevolent spirits lead the Gaddang to view the earth world as particularly hostile.  The Gaddang must then seek to establish a harmonious relationship between humans and the other natural and supernatural beings in the world.  But few Gaddang have the ability to successfully interact with supernatural forces, requiring mediums to broker between the natural and supernatural.  Male and female mediums-mengal, mabayan, and makamong-perform anitu rites and other rituals related to planting, harvesting, death, warfare, sickness, or misfortune.
Anitu to the Gaddang does not refer to an ancestral spirit, as it commonly does in northern Luzon, but a "belief in a supernatural power."  It is also understood by the Gaddang, according to Wallace, as that which is followed by all.  Wallace suggests that anitu has two basic usages in Gaddang.  First, it is a power, force, or concept through which Nanolay," but rather, "I beg to anitu."  Anitu can only be viewed as benevolent.  It is incorrect to say narakat a anitu (bad anitu).  Second, anitu also refers to seven rites of passage which all Gaddang undergo (Wallace 1970:94).
Gaddang anitu rites are rendered to cure the sick and ensure their longevity and to avoid misfortune or illness due to breach of a taboo.  Presided by the medium and usually involving the sacrifice of a pig, these rituals could also serve to indicate status and/ or the occasions for kindred socialization.
Christianized Gaddang basically adhere to Christian norms of worship and ritual and no longer practice the rites of anitu.  Pre-Christian undercurrents, however, continue to run in Christian devotions.  The belief in God, for example, closely parallels the concept of Nanolay as the all-benevolent creator.  The intercession of gods and spirits have been replaced by the veneration and appeal to saints.  Particularly potent beings among the Gaddang are the Blessed Virgin Mary (as illustrated by her role in subduing the serpent of La Torre) and San Luis Beltran, patron saint of Solano, Nueva Vizcaya.
One significant divergence between the Christian and the non-Christian with respect the religious beliefs is found in the concept of heaven or the afterlife.  While the non-Christian view of the afterlife is simply a place where all souls go, the afterlife to the Christian Gaddang is the result of a person's earthly life.  Thus, rather than see death as a misfortune, the Christian Gaddang see death as inevitable and what makes it fortunate or unfortunate is whether or not the deceased lived a good or bad life on earth.

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