613 Mitzvot
Negative Mitzvot 14
Not to swear in the name of idols

Shemot (Exodus) 23:13

Uvechol asher-amarti aleychem, tishameru; veshem elohim acherim lo tazkiru, lo yishama al-picha.
Be careful to do all things that I have said to you; and don't invoke the name of other elohim, neither let them be heard out of your mouth.

We are forbidden from invoking the name of other elohim. The word for invoke iszakar, which means to remember, to think of.

Yehoshua (Joshua 23:7)
that you not come among these nations, these that remain among you; neither make mention of the name of their gods, nor cause to swear [by them], neither serve them, nor bow down yourselves to them;

When the oath is given, the person will choose to swear in the name of something that is holy and important to him. This helps to convince others that he is sincere. We are not allowed to swear in the name of any idol or G-d.

This mitzvah refers to swearing oaths by the names of other gods. We may not engage other gods to swear by them or to use their names for any purpose. The Hebrew word for 'heard' is 'shema' which means both to 'hear' and to 'obey.' Therefore, we may not speak the names of other gods in a manner that show obedience or acceptance of their belief systems.

Shalom v'brakhot
Moreh Chizkiyah Shlomo
http://www.frontiernet.com/~toddlerville/home.html

Be libi tzavanti imratecha le ma'an lo echta lach.
(Tehillim 119:11)