As for what you say about making attempts on your lives: make your sons doctors and apothecaries, that they may take away Christian’s lives.
The Medical Swindle
The Talmud says it is forbidden for Jews to heal gentiles.
‘As for Gentiles, the basic talmudic principle is that their lives must not be saved, although it is also forbidden to murder them outright. The Talmud itself expresses this in the maxim ‘Gentiles are neither to be lifted [out of a well] nor hauled down [into it]’. Maimonides explains:
As for Gentiles with whom we are not at war … their death must not be caused, but it is forbidden to save them if they are at the point of death; if, for example, one of them is seen falling into the sea, he should not be rescued, for it is written: ‘neither shalt thou stand against the blood of thy fellow’ – but [a Gentile] is not thy fellow.”
In particular, a Jewish doctor must not treat a Gentile patient. Maimonides – himself an illustrious physician – is quite explicit on this; in another passage he repeats the distinction between ‘thy fellow’ and a Gentile, and concludes: ‘and from this learn ye, that it is forbidden to heal a Gentile even for payment…’
However, the refusal of a Jew – particularly a Jewish doctor – to save the life of a Gentile may, if it becomes known, antagonize powerful Gentiles and so put Jews in danger. Where such danger exists, the obligation to avert it supersedes the ban on helping the Gentile. Thus Maimonides continues: ‘ … but if you fear him or his hostility, cure him for payment, though you are forbidden to do so without payment.’ In fact, Maimonides himself was Saladin’s personal physician. His insistence on demanding payment – presumably in order to make sure that the act is not one of human charity but an unavoidable duty – is however not absolute. For in another passage he allows Gentile whose hostility is feared to be treated ‘even gratis, if it is unavoidable’.
The whole doctrine – the ban on saving a Gentile’s life or healing him, and the suspension of this ban in cases where there is fear of hostility – is repeated (virtually verbatim) by other major authorities, including the 14th century Arba’ah Turirn and Karo’s Beyt Yosef and Shulhan ‘Arukh.19 Beyt Yosef adds, quoting Maimonides: ‘And it is permissible to try out a drug on a heathen, if this serves a purpose’; and this is repeated also by the famous R. Moses Isserles.
The consensus of halakhic authorities is that the term ‘Gentiles’ in the above doctrine refers to all non-Jews.’
Source: The Laws Against Non-Jews http://www.bintjbeil.com/E/occupation/shahak.html