Okay, so once upon a time, a long long time ago, there were some people called Christians. These Christians lived in a time when life was not easy and many things were uncertain. They wanted to get closer to God and find a way to live a good and meaningful life.
So what did they do? Some of them decided to become monks, which means they went to live in special places called monasteries. These monasteries were like big houses with lots of rooms and places to pray and study. Monks lived there together with other monks and they shared everything they had, like food and clothes.
The very first Christian monks lived in the deserts of Egypt, long before there were any monasteries. They were called desert fathers and they lived on their own in tiny huts in the middle of nowhere. They prayed and meditated all day, trying to find peace and wisdom.
Later on, some Christian monks started to build monasteries in Egypt and other parts of the world. They had rules that they followed, called the Rule of St. Benedict, which said things like "work hard, pray hard, and don't talk too much."
These monks were really cool because they helped people! They made medicines and took care of the sick, and they even wrote books and made art. Some monks were even famous for their great wisdom and teaching, like St. Augustine and St. Thomas Aquinas.
So that's the story of early Christian monasticism, where brave people devoted their lives to God and helped others along the way.