Tefillin of Rashi and Tefillin of Rabbenu Tam
A major dispute exists regarding the order of the four passages in tefillin. According to Rashi, the order of the passages is their order in the Torah, according to Rabbenu Tam, the third passage is “Ve-haya im shamoa”, and the fourth is “Shema” * The kabbalists explained that there is value to both methods, and optimally, one should put on both types of tefillin.
