The Feast of Jubilee: Held Every Fiftieth Year
Source: TTT
Leviticus 25:8, 10
And you shall count off seven Sabbaths of years—seven times seven years—so that the seven Sabbaths of years amount to forty-nine years. / So you are to consecrate the fiftieth year and proclaim liberty in the land for all its inhabitants. It shall be your Jubilee, when each of you is to return to his property and to his clan.