Year of Jubilee

The Jubilee was a holy year observed every 50 years by the ancient Israelites. Every seventh year was a sabbatical (sabbath year), in which the land lay fallow. (that is, after the 7th sabbath year).

Biblical Reference
"You shall make the fiftieth year holy, and proclaim liberty throughout the land to all its inhabitants. It shall be a jubilee to you; and each of you shall return to his own property, and each of you shall return to his family. That fiftieth year shall be a jubilee to you. In it you shall not sow, neither reap that which grows of itself, nor gather from the undressed vines. For it is a jubilee; it shall be holy to you. You shall eat of its increase out of the field.

"In this Year of Jubilee each of you shall return to his property.

"If you sell anything to your neighbor, or buy from your neighbor, you shall not wrong one another. According to the number of years after the Jubilee you shall buy from your neighbor. According to the number of years of the crops he shall sell to you. According to the length of the years you shall increase its price, and according to the shortness of the years you shall diminish its price; for he is selling the number of the crops to you. You shall not wrong one another; but you shall fear your God: for I am Yahweh your God." (Leviticus 25:10-17)

Christian Jubilee
Various Popes have declared various Jubilee years.==