Tefilas Haderech is an important bracha, since it’s a tefillah which confirms our belief in hashgacha pratis (Divine intervention), as we are asking Hashem to protect individuals on a specific trip. Because Tefilas Haderech is so essential, it’s important to study the halachos (laws) that pertain to it.
One of the questions that contemporary rabbonim have grappled with, is this:
If a woman is having a baby on shabbos or another emergency occurs which necessitates travel on shabbos, should the travelers say Tefilas Haderech? On the one hand, in this case, traveling on shabbos is a mitzvah (of pikuach nefesh - saving a life) and safety is still required. On the other hand, individual requests are not made on shabbos, only requests for the entire community.
For example, we don’t include the usual bakashos in shemoneh esreh on shabbos because they contain individual requests. When we ask Hashem for things that concern us directly, we start worrying about what we need and this interferes with our enjoyment of shabbos. Hashem has given us shabbos as a day of rest, and when we start thinking about what needs fixing in our lives, we are likely to become restless and unsatisfied.
The sefer Ahalech B’Amisecha writes that Tefilas Haderech is recited, just like traveling on a regular day. But Rav Elyoshiv says that it cannot be recited, since we don’t make individual requests on shabbos. Rav Yitzchak Zilberstein offers a compromise solution, in which Tefilas Haderech is recited only when the travel is particularly dangerous, either because the roads are unsafe or because the car or ambulance is speeding in order to get to the hospital as quickly as possible.
May we merit safe travels at all times!