The meaning of "ethics" is hard to pin down, and the views many people have about ethics are shaky. Many people equate ethics with feelings. But being ethical is clearly not a matter of following one's feelings. In fact, feelings frequently deviate from what is ethical.
Ethics should not be tied to religion either. Most religions, of course, advocate high ethical standards. Yet if ethics were confined to religion, then ethics would apply only to religious people.
Being ethical is also not the same as following the law. The law often incorporates ethical standards to which most citizens subscribe, but consider south African apartheid, Pre-Civil War American slavery. Recently, a woman was fired for giving a 16 cent treat to a toddler. Sounds unreasonable? The worker didn't pay for it. Read More.
Being ethical is not the same as doing whatever is socially acceptable. In any society, most people accept standards that are, in fact, ethical. But standards of behavior in society can deviate from what is ethical. An entire society can become ethically corrupt; consider Nazi Germany. This creates Moral and Ethical Relativism. But rightness of wrongness cannot depend on a societies norms.