SourceFlix has posted a video about the priestly blessing on its homepage. It includes an interview of Gabi Barkay, who discovered the Silver Scroll Amulets inscribed with the priestly blessing at Ketef Hinnom in 1979.
In Numbers 6:22–27, the priests are instructed to bless the people of Israel with a three-part blessing known as the Priestly Blessing (or Priestly Benediction).
Speak to Aaron and his sons: Thus shall you bless the people of Israel.
Say to them: The Lord bless you and protect you!
The Lord deal kindly and graciously with you!
The Lord bestow His favor upon you and grant you peace!
Thus they shall link My name with the people of Israel, and I will bless them.
The words of this blessing appear on two small, silver amulets discovered in the Hinnom Valley south of Jerusalem’s Old City. The amulets date to around 600 BCE, hundreds of years before the oldest known copy of any biblical manuscript. Amulets are common throughout the ancient world and are still used today to protect the wearer from spiritual and physical evils. The inscriptions on these amulets conclude with parts of the Priestly Blessing. It is quite possible that they are not quotes from Numbers but that the Priestly Blessing was a well known liturgical passage in Ancient Israelite religion that was used both in amulets and quoted in the Book of Numbers.