By Rabbi Berach Steinfeld
The Rishonim argue that going from town to another town and thereby having the way the letters are written if it is a psul. The Rosh in 3:11 and in the Shiltei Giborim in Hilchos Sefer Torah 3 and the Meiri in Shabbos 104a they all conclude that there is no chashash in switching your letters. On the other hand, the Ramban in Meseches Shabbos writes that all the letters have a special reason why they are the way they are so switching it would make it pasul.
The question arises if one has the masoreh to use ksav Bais Yosef could he be yotzei with tefillin or a Sefer Torah written bichsav Ari or ksav Velish which is the ksav of the Sefardim? What about the opposite? The Rema in 36:1 says that if one changes the ksav it is not a problem but nevertheless there is a great inyan to be chosheish for the Ramban.
At one end we find in the name of the Gra that writes that since the mesorah of Ashkenaz is not to use the ksav Ari. We see the Chazon Ish was very makpid not to use Ari and felt that it would be le’ikuva. The Steipler in Kraina De’Igrasa 2:78 says that one should not believe those rumors that say the Chazon Ish regretted it.
On the other hand, the Maharsham in Mafteichos 2:120 says that the Sefer Torah of the Ohr HaChaim Hakadosh was written bichsav Velish. The Chasam Sofer in Yoreh Deah 66 testifies that his Rebbe Rabbi Nosson Adler’s tefillin had the letter tzaddik written bichsav Ari. The Mishna Berura in 66:5 brings the Noda BiYehuda 80 that whenever the Ramban was machmir was only the letters that were rooted in the Gemara not letters that are rooted in the Bais Yosef. The Ari himself held that all forms of ksav have their sources.
LeMaaseh, despite the fact that many say in the name of Rav Shach zt”l who advised a grandchild from the Chasam Sofer that he did not need to switch his tefillin to ksav Bais Yosef. Reb Elyashiv Zt”l held to the contrary that if a person does most of his avoda the way the Litvishhe he would need to switch his tefillin to ksav Bais Yosef. The Mesoras Moshe tells a story where a person brought Reb Moshe Feinstein to look at a letter of his tefillin. Reb Moshe said that the letter was no problem but the greatest hiddur is that the person should switch all his parshiyos to Bais Yosef.
Reb Chaim Kanievsky said that this would only apply to tefillin or mezuzos but if one listen to krias HaTorah from a Sefer Torah written in ksav Ari one is yotzei this is even though lekatchila the Sefer Torah should be written in ksav Bais Yosef. Reb Chaim added that even the Chazon Ish says one could be yotzei krias HaTorah and could even make a bracha on an Aliyah. His reasoning was that according to the Rambam one can make a bracha on a Sefer Torah that is passul. Therefore, it would not be a Bracha Levatala. Brisker Rov who held that lekatchilah one should have ksav Bais Yosef when he was on vacation in Kreinitz before the holocaust he would be yotzei from a Sefer Torah written bichsav Ari and would even get an Aliyah.
May we always be careful with what we read from that it should be kehalacha.
