Prince William delivered a reading from the Bible during the fifth annual Together At Christmas Carol Service.
The Prince of Wales shared a piece from the Gospel of Luke as he spoke to the crowd of 1,600 people.
William said: "In that region, there were shepherds living in the fields, keeping watch over their flocks by night.
"Then an angel of the Lord stood before them, and the glory of the Lord shone around them, and they were terrified.
"But the angel said to them: 'Do not be afraid. For see, I am bringing you good news of great joy for all the people.
"To you is born they in the city of David, a Savior, who is the Messiah, the Lord.
Prince William delivered a Bible reading during the service
| GETTY"This will be a sign for you: You will find a child wrapped in bands of cloth and lying in a manger.'
"And suddenly there was with the angel a multitude of the heavenly host, praising God and saying: 'Glory to God in the highest heaven, and on earth peace among those on whom his favor rests.'
"When the angels had left them and gone into heaven, the shepherds said to one another: 'Let us go now to Bethlehem and see this thing that has taken place, which the Lord has made known to us.'
"So they went with haste and found Mary and Joseph, and the child lying in the manger, thanks be to God."
The Waleses joined some 1,600 guests at Westminster Abbey
|GETTY
LATEST DEVELOPMENTS
Princess Kate smiled towards her husband as she sat alongside their children, Prince George, Princess Charlotte and Prince Louis.
The Waleses were joined by a series of other royals, including Zara and Mike Tindall and the Duchess of Edinburgh.
At the beginning of the broadcast, Kate and Charlotte played a special duet on piano.
The performance was accompanied by a voiceover from the Princess of Wales reading the letter handed to guests at Westminster Abbey.
The concert occurred on December 5
|GETTY
The pair played Holm Sound by Scottish composer, producer and multi-instrumentalist, Erland Cooper.
Mr Cooper joined the duo on the day of the performance and provided some guidance.
The composer's work is inspired by nature and connection, themes which resonate deeply with Kate.
Holm Sound was written and composed by Mr Cooper for his mother, Charlotte.
Princess Kate and Princess Charlotte played a special duet | ITV/BBC STUDIOSThe princesses often play the beautiful piece together at home, with the special moment being recorded in the Inner Hall at Windsor Castle.
The broadcast went out on ITV1 and ITVX with a repeat airing on Christmas Day morning.
BBC Studios Events and The Royal Foundation co-produced the programme, which included two special films showcasing individuals and organisations who have demonstrated love and compassion to others during difficult times.
Some 1,600 guests attended the event with the royals, including individuals from across the UK who have given their time to support others and those in need.
Our Standards: The GB News Editorial Charter