Chapter 139:4
Chanukah
4. All oils may be used for the Chanukah lights (1). Nevertheless, the
most desirable way of performing the mitzvah ("mitzvah min ha'muvchar") is
to use olive oil, similar to the miracle [of Chanukah] in the Beis
Hamikdash (Temple), which occurred through olive oil.
If olive oil is not easily available, a person should choose another oil
whose light is pure and clean. Alternatively, he should use beeswax
candles, which also produce a pure light.
Two wicks should not be wound together, because this would resemble a
torch. Instead, a single candle should be used. One should not use beeswax
from temples of idol worship, because this is considered to be repulsive
("Ma'us").
Similarly, the wicks used for the Chanukah candles may be made from any
substance. The most desirable way of performing the mitzvah ("mitzvah min
ha'muvchar"), however, is to use cotton. There is no need to use new wicks
each night. One may rekindle those used previously until they are burned up.
FOOTNOTES:
(1) There are certain inferior oils and wicks that one is not permitted to
use for Shabbos candles, because they do not light well. Since the primary
purpose of Shabbos candles is for illumination, the Sages feared that one
may inadvertently tilt or attempt to fix the flame on Shabbos, in order to
improve the light, an act which is prohibited. The Sages did not have the
same concerns regarding Chanukah lights, because one is forbidden to use
the Chanukah lights for personal use, and therefore, one would not be
tempted to fix the Chanukah flames on Shabbos. Another reason that one is
permitted to use inferior oils or wicks for the Chanukah lights, is that,
as we shall see, once one has lit the Chanukah flames, one has fulfilled
the mitzvah, and even if they become extinguished immediately after the
lighting, one is not required to rekindle the flame (Of course, one should
do one's best to use good quality oil and wicks).