The name for a chattel, of whatever origin, is _rab_, _raba_, probably derived from _rabota_, "labor." Such _rabs_ were employed in various kinds of labor, but principally in clearing the forests and cultivating the soil for their masters. Through contact with the Byzantine empire Christianity came into Russia, besides various other usages. At this epoch, a new form of servitude appeared among the Russians; perhaps it was borrowed from the old society and civilization, or perhaps it originated from a new concatenation of circumstances: it was servitude by mutual agreement or _kabala_, by which one man gave up his person, labor, and liberty to another. This kind of bondman was called _kholop_. His servitude was usually contracted for a limited time, though sometimes for life; but was never inherited. Debts could be paid by the _kabala_ writ. The poor freeman could become a _kholop_ by his own choice, or he could give up his children as _kholops_, as was then the custom among all nations, heathen and Christian. Such _kabala-kholop_, or servile person, could not be sold or disposed of in any way, as his servitude was limited in duration by specified time or by his death. Sometimes freemen choose servitude in order to escape worse conditions. Early in the domestic economy of the nation, free tenants are found who hired lands for a year or more, paying the rent (_obrog_) in money, or binding themselves to cultivate half of the land for the proprietor and half for themselves. A subsequent law prohibited any such free tenants from contracting any work or _kabala_ servitude with the landowners. The contracts of free tenants were obligatory for a year from St. George's day (April 17); but otherwise they could change their domicile or land at pleasure. The laws of the tenth and eleventh centuries stringently prohibit the infliction of any kind of corporal punishment on such free tenants. In short, these tenants had full civil liberty and full civil rights; they could own lands, and could become members of any rural or urbane community, practice any handicraft, etc. Probably it was the nobles, the rich, the higher officials, who first established chattels (_rabs_) on their lands as tillers. From these originated, beside the _rab_, the _krepostnoi kholop_, "a serf strengthened or chained to his master," _krepok_ signifying "strong," "strengthened," "attached by force"--_krepost_, "stronghold," etc. According to the laws collected or enacted by Vladimir and Yaroslaw in the tenth and eleventh centuries, _rab_ and _krepostnoi kholop_ were the descendants of prisoners of war, or of those who were bought as slaves and imported as such into Russia, and also the descendants of those who unconditionally married a slave woman; while the public, grand-ducal slaves or _rabs_ were condemned criminals.