The preoccupation with protecting boundaries between the chosen and the despised people is not limited to the Samaritan/Jewish conflict of the first century. Throughout human history, people and nations have defined themselves over against other groups.

The history of race relations in the United States, the notion of racial purity that was at the ideological heart of Hitler’s Germany, the ethnic wars that wax and wane across the Middle East, Africa, Asia, and Europe all have their roots in the same fears that divided Jews from Samaritans: the fear of contamination (Jn 4:9c), the fear of sharing (Jn 4:20) one’s gift and privileged call (Jn 4:20) with others.

from The NIBC for John’s Gospel