So what precepts are essential to your faith ravens? What disagreement is so drastic you cannot in good conscience fellowship with the person as a fellow believer? If you have not thought this through, you will have to interview every person you meet to see if they are acceptable or not.
tec, the flaw in your argument is the same one the Witnesses apply to the Bereans. Witnesses assume they have the truth so they are sure the Bereans would study them out to find them to be so. The thought that they might not...never crosses their mind.
By the way, who is a First Nations person and who is not gets more complicated. There's been plenty of cross-pollination way, way back. The US tends to declare a person a Native American based on percentage of "blood". Canadians do not, that being a little too close to the old question, "who is black". A Federal Court Judge here in Canada has concluded that anyone who considers himself or identifies herself as First Nations, is.