According to Serbian scholar Veselin Čajkanović, the zapis is inherited from Slavic paganism, the pre-Christian religion of the Serbs, in which it had been used as a temple.
The selected tree becomes a zapis through the rite of consecration performed by a Serbian Orthodox priest, in which a cross is inscribed into its bark.
[1] The zapis plays an important role in rites connected with the festival known as krstonoše, meaning "crossbearers", which is publicly celebrated within the village to supplicate God for protection against destructive weather conditions, as well as to ensure a good harvest.
[3] During the service, the priest and the man elected for the host of the krstonoše hold together a round loaf of bread, rotate it three times counterclockwise, and break it into two halves.
[1] Some villages and hamlets in Serbia also observe a festival commemorating a disaster that has befallen the settlement, such as a flood, fire, or lightning strike.
[2] In his study on the cult of trees among ancient Serbs, ethnologist Veselin Čajkanović states that the zapis is inherited from Slavic paganism, in which it had been used as a temple.
A zapis is primarily selected from oaks, the trees associated with Perun—the thunder god of the ancient Slavic religion.
Each was surrounded with icons, after which a priest read from a Gospel facing the tree, sprinkled it with holy water, and then put the consecrated bread under its bark.
In other areas, there was a custom of placing a cross, a fireplace, and a table made of stone by a tree on a hillock near a river or lake.