December 1-December 24
Advent is a season of expectation and preparation, as the Church prepares to celebrate the coming (adventus) of Christ in his incarnation, and also looks ahead to his final advent as Judge at the end of time. The readings and liturgies not only direct us towards Christ’s birth, they also challenge the modern reluctance to confront the theme of divine judgement. The characteristic note of Advent is therefore expectation, rather than penitence.
Church decorations are simple and spare, and purple is the traditional liturgical color. In the northern hemisphere, the Advent season falls at the darkest time of the year, and the natural symbols of darkness and light are powerfully at work throughout Advent and Christmas. The lighting of candles on an Advent wreath was imported into Britain from northern Europe in the nineteenth century, and is now a common practice.
-Times and Seasons, The Church of England