# 1328 Take Offense
( Re- question 1327). Thank you for your comprehensive answer on using an electronic key-card on Shabbat. I have two more questions. You mentioned that there is at least a rabbinic prohibition for using the card. What exactly is the offense based on?
Besides the known opinion of the Chazon Ish, that activating an electric circuit is boneh and constitutes a Biblical prohibition, there are different views and opinions in the Poskim.
Beis Yitzchok (Y.D. 2: 31: index) and others maintain the proscription of closing and activating an electric circuit is molid (Making changes to an object or substance. Creating a new entity on Shabbos). He writes: Creating a current flow (molid zerem) is rabbinically forbidden because in doing so one has created something new - a functioning appliance. (See Minchas Shlomo pp. 71-74; Tzitz Eliezer 1:20:10, Tz’lach Hachadash, Kuntres Acharon 1).
Poskim also assert that activating any electrical equipment involves “makkeh bepatish,” literally, striking with a hammer; an act of completing an object and bringing it into its final useful form. These Poskim cite as precedent those who prohibited winding a watch for this reason. (Chazon Ish, O. H. 50: 9; Mishp’tei Uziel 1: 13; Tzitz Eliezer 6: 6; Edus Leyisarel (Rabbi Y. E. Henkin) p. 121. (Rabbi Henkin states that perhaps only a Rabbinic prohibition is involved. The prohibition of metaken mana, is a sub-prohibition of makkeh bepatish).
Rabbi A. Bartfeld as revised by Horav Shlomo Miller Shlit”a
Answered by: Hagaon Rav Shlomo Miller Shlit'a
Published: May 19, 2017