Purple has traditionally been the primary color of Advent, symbolizing repentance and fasting. Purple is also the color of royalty, demonstrating the anticipation and reception of the coming King celebrated during Advent. Today, however, many churches have begun to use blue instead of purple, as a means of distinguishing Advent from Lent.
Pink (or rose) is also one of the colors of Advent used during the third Sunday. It represents joy or rejoicing and reveals a shift in the season away from repentance and toward celebration.
White is the color of the center Advent candle, representing purity. Christ is the sinless, spotless, pure Savior. Also, those who receive Christ as Savior are washed of their sins and made whiter than snow.