'Perpetuity' in the Bible

" 'But the land must not be sold in perpetuity, because the land [is] mine, because you [are] aliens and temporary residents with me.

But if it is not redeemed {before a full year has passed}, then the house that [is] {in the walled city} shall belong to the buyer in perpetuity throughout his generations; it shall not go out [of the buyer's hand] in the Jubilee.