See especially Romans 13:8-9
Romans 13:8 - 14
ESV - 8 Owe no one anything, except to love each other, for the one who loves another has fulfilled the law. 9 For the commandments, "You shall not commit adultery, You shall not murder, You shall not steal, You shall not covet," and any other commandment, are summed up in this word: "You shall love your neighbor as yourself.
For follow-up discussion and general commentary on the topic. Comments are sorted chronologically.