What is the religious painting it the church?

There are many religious paintings in churches. In Orthodox churches the stylised paintings of holy scenes are called Icons (or Ikons). Just like the little pictures on a computer screen you click on to start programs or open files. The religious pictures had this name for a long time before computers were invented.

In a Catholic church there may be 14 pictures around the walls of the church depicting scenes from the trial and execution of Jesus. These are called the Stations of the Cross. They are often numbered in roman numerals I, II, III, IV and so on. 14 is XIV.

Many painters used religious themes in their painting and many hang in churches and galleries around the world.

Some artists painted directly onto wet plaster so that the painting is part of the wall and not hung on it. These are called frescoes (plural of fresco, meaning fresh in Italian - relating to the fresh/damp plaster the artist has to work on).