In Jewish law, the Jubilee year follows a series of 7 sabbatical years. I can't remember all the ways these differ from the jubilee, but they are somewhat less gigantic. Since it follows a cycle of seven sevens (49 years divided into seven) it is presumably related to the messianic number eight. A guess: that property reverts to its original owner is, in that sense, connects with the notion that everything is God's. Also, Jewish civil law discusses the effect of the Jubilee cycle on the value of property with relation to contracts.