What were the means by which the christian movement defined orthodox belief and established ecclesiastical authority in late antiquity?

What were the means by which the christian movement defined orthodox belief and established ecclesiastical authority in late antiquity?

How did the roman catholic , orthodox, and protestant traditions within Christianity emerge from the "catholic" or "universal" Christianity of the first millennium? what were the main factors that contribute to the formation of these traditions?

What are the seasons and holy days of the liturgical year? what is their significance?