Like the Aztec and Inca who came to power later, the Maya believed in a cyclical nature of time. The rituals and ceremonies were very closely associated with celestial and terrestrial cycles which they observed and inscribed as separate calendars. The Maya priest had the job of interpreting these cycles and giving a prophetic outlook on the future or past based on the number relations of all their calendars. They also had to determine if the "heavens" or celestial matters were appropriate for performing certain religious ceremonies.
The Maya practiced human sacrifice. In some Maya rituals people were killed by having their arms and legs held while a priest cut the person's chest open and tore out his heart as an offering. This is depicted on ancient objects such as pictorial texts, known as codices. It is believed that children were often offered as sacrificial victims because they were believed to be pure.
Much of the Maya religious tradition is still not understood by scholars, but it is known that the Maya, like most pre-modern societies, believed that the cosmos has three major planes, the underworld, the sky, and the earth.
The Maya underworld is reached through caves and ball courts. It was thought to be dominated by the aged Maya gods of death and putrefaction. The Sun and Itzamna, both aged gods, dominated the Maya idea of the sky. The night sky was considered a window showing all supernatural doings. The Maya configured constellations of gods and places, saw the unfolding of narratives in their seasonal movements, and believed that the intersection of all possible worlds was in the night sky.
Maya gods were not separate entities like Greek gods. The gods had affinities and aspects that caused them to merge with one another in ways that seem unbounded. There is a massive array of supernatural characters in the Maya religious tradition, only some of which recur with regularity. Good and evil traits are not permanent characteristics of Maya gods, nor is only "good" admirable. What is inappropriate during one season might come to pass in another since much of the Maya religious tradition is based on cycles and not permanence.
The life-cycle of maize lies at the heart of Maya belief. This philosophy is demonstrated on the belief in the Maya maize god as a central religious figure. The Maya bodily ideal is also based on the form of this young deity, which is demonstrated in their artwork. The Maize God was also a model of courtly life for the Classical Maya.
It is sometimes believed that the multiple "gods" represented nothing more than a mathematical explanation of what they observed. Each god was literally just a number or an explanation of the effects observed by a combination of numbers from multiple calendars. Among the many types of Maya calendars which were maintained, the most important included a 260-day cycle, a 365-day cycle which approximated the solar year, a cycle which recorded lunation periods of the Moon, and a cycle which tracked the synodic period of Venus.
Philosophically, the Maya believed that knowing the past meant knowing the cyclical influences that create the present, and by knowing the influences of the present one can see the cyclical influences of the future.
Even in the 19th century, there was Maya influence in the local branch of Christianity followed in Chan Santa Cruz. Among the K'iche's in the western highlands of Guatemala these same nine months are replicated, until this very day, in the training of the ajk'ij, the keeper of the 260-day-calendar called ch'olk'ij.