How do husband and wife or neighbors fulfill the whole law?
Paul teaches that when a husband and wife, or one neighbor with another, always seek the other person's highest good in whatever they do, they fulfill the whole law. This love is not mere physical attraction but seeking the other person's highest good.
Les explains that the love Paul commands is not erotic love or Hollywood's idea of love; it is a love that seeks the other person's highest good. Applied to a husband and wife or a neighbor with a neighbor, whenever they always attempt in whatever they do to seek the other person's highest good, Paul says they are fulfilling the whole law. Les also notes that this cannot be done simply on the basis of commanding, because we never really grow up.