The Torah forbids us to harm or cause suffering to others. Even from a selfish perspective, we should be careful not to harm others, since we will ultimately suffer because of it.

Some guidelines:

* Refrain from insulting others.

* Refrain from talking negatively about others, unless it is necessary for a practical and constructive purpose.

* Refrain from lying to others.

* Refrain from deceiving others in financial matters.

* Refrain from causing others pain or unpleasantness through actions or words.

* Refrain from causing others financial losses. The money of others should be as dear as our own.