Swing State

Dayan Daniel Dombroff

May 13, 2021

Q I hung a swing from a tree in my backyard by screwing a two-by-four to the tree and connecting the swing to the beam. May the swing be used on Shabbos?

A It is forbidden to make use of a tree on Shabbos (e.g., by climbing on it or placing an item on it), which is known as mishtameish b’ilan. Chazal were concerned that one who uses a tree may unintentionally pull off a fruit or branch from the tree, violating the issur d’Oraisa of kotzeir (harvesting). The prohibition also includes using an item attached to a tree (e.g., climbing a ladder leaning on the tree), known as tzedadim (sides). On the other hand, one may use an object attached to another object attached to a tree (e.g., placing an item inside a basket hanging on a hook attached to the tree). This is known as tzidei tzedadim (sides of sides) and is not called using the tree.

Consequently, it is forbidden to tie a swing directly to the tree and then use it on Shabbos. But you tied the swing to the two-by-four, which is attached to the tree, so it would be considered tzidei tzedadim. However, if the tree moves when someone rides on the swing, it is considered using the tree and forbidden.

Connecting two trees with a zipline has become popular. It would seem at first glance that riding such a zipline would be permitted on Shabbos as tzidei tzedadim if the ends were connected to the trees with intervening wooden beams, the way you installed the swing.

But this may not be the case. Chazal also prohibited using animals on Shabbos, due to the concern that one might tear a branch off a tree to strike an animal. The Mishnah Berurah (305:67) prohibits having animals pull a wagon with a board attached to it to carry a load; because the wagon/board combination is one keili, this is not tzidei tzedadim. Our case would appear similar, but the specifics of each case matter.