What does Genesis 24:6 mean?

Abraham has asked his servant to swear to find a wife for his son Isaac among his extended family back in his old homeland. The servant has asked what to do if a woman cannot be found who is willing to live in Canaan. Should Isaac move to Abraham's old homeland to live in order to be married to one of the women of his extended family? That's a reasonable question, since Abraham is so absolutely set on Isaac marrying a woman from that region.

Here Abraham makes his position clear: in no uncertain terms, Isaac cannot be allowed to go to Mesopotamia. In fact, Abraham instructs the servant not to take Isaac back to that land. Isaac's place is in the Promised Land of Canaan. This is the home of Abraham's future offspring—period. Isaac must not be allowed to leave and, by implication, risk settling outside of Canaan among Abraham's extended family.

Abraham has established why this mission is so critical. Isaac must not marry into a Canaanite family and thus be assimilated into the Canaanite people. This is a spiritual issue, not a racial one: Abraham does not want to risk the identity of Abraham's descendants as God's chosen ones. But Isaac also must not return to Abraham's people and settle outside of the land of promise, which would also risk the family's loss of identity as those who belong to God.

Only one path would work: Isaac must marry a woman from Abraham's people and also live in the land of promise as a people living among, but separate from, the Canaanites.