414. The Holiness of Tefillin
Tefillin, Mezuzah v’Sefer Torah 4:24
One may not engage in marital relations in a room with tefillin or a Torah scroll unless they are removed or placed into a container which is then placed into a second container that is not designated for them. If the second container is designated for them, then even ten containers would be considered like one. If a person puts them in two containers, he may place them at the head of his bed, between a bolster and a pillow, as long as they are not under his head. This is true even if his wife is in bed with him.
Tefillin, Mezuzah v’Sefer Torah 4:25
The holiness of tefillin is very great. As long as one has tefillin on his head and arm, he will be humble and in awe of God, and he will not be drawn towards frivolous activities or empty speech. His thoughts will not turn to evil; rather, he will direct his heart towards matters of truth and justice. Therefore, one should try to wear tefillin throughout the day, because this is the actual mitzvah. Rav, student of Rav Yehuda HaNasi, was praised that he was never seen walking four cubits without words of Torah, tzitzis and tefillin.