I heard that one is forbidden to tie a sailors
knot on Shabbos, but are not all knots forbidden?
In order to answer
your question we need to lay down the foundation of this sugya. The pertaining Mishna
and gemora can be found in Shabbos 111b-112a. We find that the major Rishonim
differ over the understanding of the sugya and hence the ramifications greatly
subdivides the tying of knots on Shabbos into three categories: 1) Knots that are
Biblically prohibited to tie, 2) Knots that are Rabbinically prohibited to tie and 3)
Knots that are permitted to tie.
Ossur midoraisso: the gemora
says ???????? (bidushkepi).
Rashi explains that the leather worker would insert a strap into the shoe and tie
it permanently into place. Since this knot is a permanent one, it is ossur midoraisso.
Ossur midrabanan: the gemora says
bidrabanan (the students shoes). Rashi explains that the
students would tie their shoe straps loosely to their legs enabling the shoes
removal without having to untie the knots. Nevertheless they were not permanent knots,
because when walking in mud they would untie the knots and fasten the straps tightly to
their legs so that the shoe would not stick to the mud and come off.
????? (Bnei Mechoza). Rashi explains
that the people of Mechoza were meticulous with their clothing and would tie the
straps tight to the point that they could not be slipped off the leg. Therefore it was not
a permanent knot since they would have to fasten and unfasten the shoe straps to their
legs on a daily basis.
The Rif and
the Rambam add another factor craftsmanship. They see in the sugya
that for a knot to be Biblically prohibited it must be the type tied by craftsmen. The
underlying feature of such a knot is its strength.
So where does the sailor knot come in?
The sailor knot is a
craftsmans knot par excellence and would definitely contribute towards a
perpetrator being guilty of a Biblical transgression. However time is a factor as well, as
we will see.
The other factor is time
and according to Rashi and the Rosh it is the only factor.
A knot tied forever
kayama is ossur midoraisso.
Longer than a week
or 24 hours (two opinions) is ossur midrabanan.
Less than a week or
24 hours (the respective opinions) is permitted.
The synopsis is as
< 24 hours
< a week
Biblical according to all
and Rambam Rabbinical
and Rambam Rabbinical
Rashi Rosh permitted
and Rambam rabbinical
Rashi Rosh Biblical
and Rambam machlokes
Rashi Rosh Rabbinical
There are two
opinions as to the permitted time factor and Lchatchila one should not
tie even a simple knot on Shabbos if he intends untying it after 24 hours.
Which of the above opinions is the halacha?
Aruch (Mechaber) rules according to the Rif and the Rambam and
The Rama rules according to Rashi and The Rosh, at least lchumra.
Accordingly one may only tie a simple knot within the permitted time bracket.
Are most knots permitted because after all most
knots are not craftsmens knots?
Things are not so
simple. The poskim hold that a strong double knot is classed as a craftsmans
knot due its sturdiness and strength; hence one may not tie a double knot even for less
than 24 hours.
What about a double knot tied in a womans
kerchief or the knot in the handkerchief tied around ones neck, are they also
Since the main
feature of a craftsmans knot is its strength and these particular knots are not tied
sturdily, one is permitted to loosely tie them. This would seemingly not
apply to tying shoelaces in a double knot owing to the fact that they are fastened