SIGN THE PETITION
The Talmud is very complicated, not every statement is a law, sometimes it is commentary or the opinion of a certain Rabbi, sometimes a stipulation or refutation, however the quotes below should give you a good idea about Talmudic reasoning on certain issues.
According to the Talmud Jews are not to marry non-Jews unless they convert, at which time they are considered a "different person".
TALMUD: JEWS MUST NOT MARRY “HEATHENS” OR “SLAVES” UNLESS THEY CONVERT
Will you suggest [that what is meant is]: Whether your father is told, ‘You may keep her’ or whether your father is told, ‘Let her go’. the All Merciful said, ‘She is thy sister’, to include his sister from a slave and a heathen! — Scripture stated, The father’s wife’s daughter, only she with whom your father can enter into marital relationship, but a sister from a slave or a heathen is excluded. And what ground is there for this? — It is logical to include those subject to kareth since generally their betrothal is valid. On the contrary! A slave and a heathen should have been included since on embracing the Jewish faith, betrothal with himself is also valid! — When any of these adopts the Jewish faith she becomes a different person. (Babylonian Talmud, Yebamoth 23a)