Scientists have identified a specific, love-inducing, trust-building chemical called Oxytocin. Psychologists refer to it as the "hormone of love." When oxytocin is present in our brain, we want to reach out to help and bond with other people. However, a 2011 New York Times article explains that apparently this "love hormone" has its limits. Recent research suggests that human oxytocin produces a brand of "love" that only extends to people in our "in-group." In other words, in sinful human beings oxytocin unleashes a narrow, ethnocentric kind of love—a love that extends to "our kind of people."

In recent studies from the Netherlands, a number of students were given doses of oxytocin and then presented with hypothetical dilemmas. In one scenario, Dutch students were asked "whether to help a person onto an overloaded lifeboat, thereby drowning the five already there." In another scenario, the Dutch students were asked whether to save "five people in the path of a train by throwing a bystander onto the tracks." The five people who might be rescued were nameless, but the person who might be sacrificed was given either a foreign or a Dutch name. Students who sniffed oxytocin prior to these tests were much more likely to favor their own kind and sacrifice ethnic outsiders.

The study concluded that oxytocin only increases our love and loyalty for people in our in-group. Conversely, it makes us more likely to exclude those who aren't like us. Clearly, in our fallen state, our love doesn't stretch very far.

How radically different is the love of God! Christ specifically healed, embraced, and then died for blatant outsiders—even his enemies—not just insiders. Then Christ calls us to love enemies and outsiders.