Introduction:
Christianity, with its origins in the Middle East, spread throughout Europe and had a profound impact on the society and culture of the continent. The introduction of Christianity brought about several changes in the practice and life of European society, which can be discussed as follows:

1. Religious Transformation:
- Pagan religions, prevalent in Europe before the spread of Christianity, were gradually replaced by the new faith.
- The belief in one God, as presented in Christianity, led to the abandonment of polytheism.
- Conversion to Christianity became a significant aspect of European society, and it influenced various aspects of people's lives, including their daily rituals and customs.

2. Social and Cultural Changes:
- Christianity emphasized the importance of charity, compassion, and love for one's neighbors, leading to a shift in social values.
- The idea of sin, repentance, and forgiveness became prominent, affecting the moral and ethical conduct of individuals.
- The Christian concept of monogamy and the sanctity of marriage influenced European society, leading to the decline of practices such as polygamy and concubinage.
- The Church played a vital role in education, leading to the establishment of schools and universities, which contributed to the intellectual development of European society.
- The spread of Christianity also led to the construction of magnificent churches and cathedrals, which became the center of community life and fostered the development of art and architecture.

3. Political Changes:
- The Church and its leaders gained significant influence over political affairs, leading to the establishment of the Holy Roman Empire and the Papal States.
- The concept of divine right, where rulers were believed to be appointed by God, legitimized the authority of monarchs in European society, creating a strong bond between religion and politics.
- The Church also played a crucial role in the feudal system, acting as a unifying force and providing stability during times of political upheaval.

Conclusion:
In conclusion, the introduction of Christianity in European society brought about significant changes in various aspects of life. It transformed religious practices, influenced social and cultural values, and had a profound impact on political structures. The influence of Christianity can still be seen in European society today, shaping its traditions, values, and institutions.