Lev 25:8-10
8 ‘You are also to count off seven sabbaths of years for yourself,
seven times seven years, so that you have the time of the seven sabbaths of years, namely,
forty-nine years. 9 ‘You shall then sound a ram’s horn abroad on the tenth day of the seventh month; on the day of atonement you shall sound a horn all through your land. 10 ‘You shall thus consecrate the
fiftieth year and
proclaim a release through the land to all its inhabitants. It shall be a jubilee for you, and each of you shall return to his own property, and each of you shall return to his family.