Hilchos Shabbos

In the previous shiurim we discussed opening food packets and the issues of tearing and k’li making. As mentioned, a Rav must be referred to as to the l’ma’ase of these halachos, as there is much controversy over this matter.

            What about opening tin cans?

             In today’s affluent society, most tin cans share the same destiny as potato chip packets and are discarded upon depletion. The Chazon Ish [1] commences saying that when one does not intend using the can, opening it is not called making a k’li.

However he adds, “Since many people intend using the tin can for storing soaps, nails etc, there is room to prohibit the opening of the can lest he has in mind to use it”. Many poskim [2] say that the Chazon Ish was only referring to his times when tin cans were often used for storing etc, but nowadays even the Chazon Ish would agree that there is no problem opening a tin can that one does not intend using. Nevertheless, certain poskim say that one should puncture one side of the can and open the other side thus avoiding the problem of making a k’li, because one will surely discard a can with a hole in the bottom.

Rav Shlomo Zalman Auerbach says [3] that one may open a tin can in the normal fashion, as it is discarded after use. In order to avoid this issue one should before Shabbos open tin cans one intends on using.

            What is the halacha with regards to pop-up soda cans?

             The Mishna Shabbos 146a teaches us that one is permitted to break open a barrel on Shabbos to retrieve its contents, provided that one does not create a ‘nice’ opening. The Ran explains that making a nice opening converts the barrel into a k’li. In other words, it is not the physical nicety that is forbidden, rather it is the objective achieved by creating a ‘nice’ opening.

Accordingly, one would be permitted to fashion a ‘nice’ opening if the vessel would not become a k’li.

We brought opinions in the previous sheet that learn that one may open packets, tin cans etc. and it is not called ‘fashioning a k’li’ because the container is discarded upon depletion. Even though opening a tin can is a ‘nice’ opening, nevertheless since the can is not reused it is not called a k’li and may be opened regularly (according to the lenient opinion).

We can correlate the same to a pop-up soda can. Even though the opening fashioned when pulling the tab is a ‘nice’ one, since the can is not reused upon depletion, it is not called making a k’li and may be opened normally on Shabbos. [4]

Others may disagree and say that after all one is fashioning a nice opening and one may not open it in the normal manner on Shabbos.

According to the stringent opinion who prohibits opening such a can on Shabbos, a solution would be to pry open the tab just enough to allow the insertion of a straw but not enough to enable practical use of the can.

            What’s with the boxes of fresh juice that have a small hole covered with aluminum foil?

            The Mechaber says that a sealed opening above the dregs is not a proper seal and may be reopened on Shabbos. [5]

Hence, everyone agrees that the foil or paper may be pierced on Shabbos because the opening is already there and one is merely removing its covering.

            Is one permitted to remove the paper or aluminum foil covering a coffee jar?

            The Bais Yosef [6] quotes a Tosefta that says the following:

One may slash the leather covering the mouth of a barrel provided that one does not intend to form a spout.

A coffee jar is sealed with a piece of paper or aluminum foil that is torn off before the initial use. The Tosefta seems to be referring to a case very similar to ours and one is therefore permitted to tear off the paper sealing the jar.

The Tosefta stipulates that one not form a spout with the leather atop the barrel. This means [7] that one may rip the leather haphazardly taking care not to form a spout with the torn pieces. When entirely removing the piece of paper stuck to the coffee jar or when removing the aluminum foil one is not forming a spout, rather one is merely exposing the opening of the jar. Rav Sternbuch shlita points out that tearing the paper in a way that it can still be used is forbidden.

            What can you tell me about opening soda bottles or grape juice bottles?

            The problem with opening soda bottles or grape juice bottles is the removal of the ring attached to the top thereby creating a k’li – the cap. We must differentiate between the metal caps and the plastic ones because they are manufactured differently and hence carry different halachic ramifications. Here too the poskim disagree as to whether it is permitted or not.

Metal Caps – we are referring to the metal caps sealing a grape juice or wine bottle, where the attached ring is also metal. Here there is almost a consensus [8] to prohibit the opening. The cap as it is on the bottle cannot be used to close other bottles (if hypothetically you would remove the cap without detaching the ring) and only upon detaching or widening the ring it can be used. By detaching it you are fashioning a k’li.

The solution would be to puncture the cap with a knife etc. and then open it thereby revoking its use as a k’li, being that such a cap is not used for other bottles and is discarded.

Plastic caps or rings – Many authorities attribute the same features with these caps as with the metal ones and forbid opening them on Shabbos. Others distinguish between the two. The lenient opinion holds that since the plastic cap is screwed on in the factory with the ring attached, unlike the metal one which is shaped on the bottle and cannot be screwed on with the ring attached, in effect it is already a k’li before the ring is detached and detaching the ring does not fashion a k’li. Accordingly one is permitted to open such a cap in the regular manner. [9]