It has often been demonstrated that people who have been cut off from every manifestation of their Jewishness, living virtually as gentiles in every respect, when faced with the ultimate test of their Jewishness have chosen to endure even the worst deprivations and tortures, and to die Al Kiddush HaShem, as a final expression in this life of the Holiness of the Almighty, and the oneness of His Torah and His people.
Among other peoples and other nations there have also been men and women who gave their lives willingly for their beliefs.
But it has been as a rule those few who had a high degree of spirituality and devotion to their faith.
Not so the Jews: even the most distant, bereft of spirituality, carries within himself this supranatural capacity to renounce life rather than to renounce God.
Again, it is apparent that this force derives not from the life-long efforts of highly motivated Jewish believers, but from something built into the fiber of the Jewish soul.
–Rabbi Adin Steinsaltz