The third candle is the Shepherd Candle or Candle of Joy. We are reminded of the joy we have in Jesus, and that we are now at the midpoint of Advent, halfway through our preparation and close to Christmas.
This candle is pink/rose instead of purple, which shows a lessening emphasis on penitence as attention is turned more to the celebration of the season.
Rejoice in the Lord always. I will say it again: rejoice! Let your gentleness be evident to all. The Lord is near. Do not be anxious about anything, but in every situation, by prayer and petition, with thanksgiving, present your requests to God. And the peace of God, which transcends all understanding, will guard your hearts and your minds in Christ Jesus. Philippians 4:4-7