Normative ethics asks what ultimately makes an action right or a life good. Four broad answers compete for the same ground: that rightness is fixed by rules or duties, by the consequences an action produces, by the character and virtues of the agent who acts, or by what God commands. A single hard case — a costly promise, a risky rescue — is judged differently depending on which of these is taken to carry the weight.
This is a question about the standard of conduct. Its three most widely taught answers are deontology, consequentialism, and virtue ethics; Divine Command Theory grounds rightness in God's commands instead.