If a journey starts during the day and continues into the night, must one recite “tefillat ha-derech” (Wayfarers’ Prayer) again after nightfall?
The Shulhan Arukh (Orah Haim 110,5) rules as follows: “It should be recited only once in a day, even if one stops in a city in the middle of the day. But if his intention was to sleep over in the city and thereafter he changed his mind and left, in order to go out of the city or to return home – then he must recite it over again.”
In other words, tefillat ha-derech is recited once in the day for all the journeying of that day. However, if a person stops somewhere with the intention of that being his final stop for the day, then if he changes his plans and takes to the road again, he must recite it over again.
Hence we may deduce that the recital of tefillat ha-derech is dependent on the person’s subjective intentions. As soon as he completes his journey, or goes to sleep for the night, he ceases to concentrate on the journey, and the blessing that he recited in the morning is no longer valid. Since the prayer is dependent on the person’s intentions and consciousness, if he leaves for a journey during the day and the same journey continues into the night, he need not recite it over again. If a person leaves for a journey before daybreak, he should recite the prayer as he departs. (The Peri Megadim seems to indicate that it should be recited specifically by day – i.e., when it is light.)
A person who will be journeying for several consecutive days and nights, or who sleeps over in a place that is not inhabited, should – according to the Ridbaz and the Kitzur Shulhan Arukh – recite tefillat ha-derech with the concluding blessing on the first day, and on the other days without the concluding blessing. The Arukh ha-Shulhan maintains that the full tefillat ha-derech, including the blessing, should be recited on every day of the journey.