Why did the editors of the Bible choose only four gospels?

Answer 1

In modern terminology, the term 'editor' usually means an individual or group in this case, who makes amendments to a work to fit either a space or ideological criteria (excluding grammatical amendments).

The 'editors' in this sense were the early church believers who themselves knew first-hand in many cases whether the events carefully recorded in the Gospels were true or not. Since they were written so close to the actual events and there were many opponents living who were also knowledgeable about these events they had to be careful in what they recorded.

For this reason, other accounts of Jesus' life which contain factual errors or unnecessary embellishments were excluded. It was also important that they had a degree of apostolic authority. Matthew and John were apostles, while Mark recorded things from Peter the apostle and Luke from Paul and others.

Their 'editorial criteria' was thus essentially truth about both Jesus' life and teachings, although they were obviously written from different perspectives, with different natural styles and for different audiences. The others were excluded essentially for this reason.