Comparing Matthew, Mark, And Luke

These synoptic gospels, Matthew, Mark, and Luke, often tell the same story but have a slight variation. Matthew appears to be the shortest “story” and also seems to be a summary. Mark and Luke tend to go in more detail but also have many differences. These stories are the same because they talk about demon-possessed men. There are two demon-possessed men in Matthew, while in Mark and Luke it has one demon-possessed man. The settings are also very similar; the demon(s) come from the tomb to Jesus in Matthew and Mark, while in Luke the demon comes from the town to Jesus (it also states that the demon lives in the tomb). As the stories progress, the demons each ask Jesus, “what do you want with us, Son of God?” (Matthew). But in Mark and Luke,
After the people ask Jesus to leave, Jesus says in return, “Go home to your own people and tell them what the Lord has done for you.” Why wouldn’t it be stated in Matthew about what the Lord has done for them? It also seems different that Matthew’s story is so much shorter than Mark and Luke. This makes sense because each of them could have remembered the story differently; Matthew just didn’t remember a whole lot. Why would the village people ask Jesus to leave their region? Were they afraid of the demon that Jesus had extracted from the men? Why wouldn’t they celebrate with Jesus and call him a hero for casting out the demons? Also, what is the significance in the name Legion? After reading closely and searching the internet, Legion is a group of demons which is stated in Mark and Luke. With these stories, when each one is written, why wouldn’t Matthew, Mark, and Luke get together and discuss what happened so they don’t miss any detail? Or do we want them to write their stories as is and see the differences and similarities they come up with? There is one difference that was not stated in Mark or Matthew. In Luke, the demons begged Jesus not to order them to the Abyss. What is the Abyss? Is it a place of no return? What is so bad about the “abyss”? After doing some research, I found that abyss is basically a bottomless pit, in which it receives not daylight (Lewis). The demons don’t want to end up there because they will no longer be able to take over human bodies or wreak havoc on the earth. Basically, sounds like hell, and if I were the demons, I definitely would not want to go there (or go back for that