The first mention that we meet concerning circumcision is in Genesis. It is the command of God to Abraham; in establishing the covenant with him, He said to him: "This is my covenant, which ye shall keep between me and you, and thy seed after thee: every man-child among you shall be circumcised. And ye shall circumcise the flesh of your foreskin; and it shall be a token of the covenant betwixt me and you" (Gen. xvii, 10, 11). It was also ordained that this should be extended to servants belonging to Abraham and his seed, as well as to their own children; and that in case of children it should be done on the eighth day after birth.[54] This was appointed as an ordinance of perpetual obligation on the Hebraic family, and its neglect or omission entailed being cut off from the people (12, 14). In compliance with this ordinance, Abraham, although in his ninety-ninth year, circumcised himself and all his slaves, as well as his son Ishmael. Slaves by purchase were circumcised,[55] as were any strangers, who were also circumcised before being allowed to partake of the passover or to become Jewish citizens. It was to be observed by all heathens who became converted to the Jewish faith. During the wanderings in the wilderness circumcision was not practiced, but Joshua caused all to be circumcised before they entered the promised land.[56] The old Hebrews strictly followed the injunction to circumcise on the eighth day, and of such importance in a religious sense was this rite in their estimation that even when the eighth day fell on the Sabbath the eighth day ordinance was observed. The ordinance, however, was not blindly arbitrary, as rules were laid down for exception. For instance, whenever a family had lost two children through circumcision it did not become obligatory on that family to circumcise the third child, who was however considered as entitled to all the benefits of the congregation or of the Hebraic religion, just the same as if he had been circumcised. Again, Maimonides, or Moussa Ben Maimon, a celebrated physician and rabbi, born in Cordova in the year 1135 A.D., among his works on medicine, has left directions in regard to circumcision which have been the guides of the _mohels_. Among the Hebraic physicians it was considered that the child partook of the constitutional strength or feebleness of the mother; hence the rule above mentioned, in regard to exemption to circumcision, only was in operation when the two who had formerly died belonged to the same mother as the third one, who would thereby be exempt; but if the two children had belonged to another woman, and this third child of the father was not from the same mother, the rule did not exempt. The third child of the mother who had previously lost two infants at the rite was, however, to be circumcised when arrived at adult age, provided no further counter-indication occurred. The opinion that the mother gave the constitution to the child