Book Name:Musafir ki Namaz
four [Rak’āt] were declared Farḍ but the Ṣalāĥ during a journey was left in the initial state [with two Rak’āt of Farḍ].’ (Ṣaḥīḥ Bukhārī, vol. 2, pp. 604, Ḥadīš 3935)
Sayyidunā ‘Abdullāĥ Bin ‘Umar رَضِىَ الـلّٰـهُ تَعَالٰی عَـنْهُمَا has narrated that the Noble Prophet صَلَّى اللهُ تَعَالٰى عَلَيْهِ وَاٰلِهٖ وَسَلَّم declared two Rak’āt obligatory for the Ṣalāĥ offered during a journey saying that it is complete [Ṣalāĥ], not incomplete. That is, even though apparently two Rak’āt were reduced but two Rak’āt are equal to four Rak’āt in terms of reward. (Sunan Ibn Mājaĥ, vol. 2, pp. 59, Ḥadīš 1194)
صَلُّوۡا عَلَى الۡحَبِيۡب صَلَّى اللّٰهُ تَعَالٰى عَلٰى مُحَمَّد
Distance of Shar’ī journey
By Sharī’aĥ, a traveller is the person who has left his place of residence, i.e. city or village, with the intention of travelling 57½ miles (i.e. approximately 92 kilometres). (Derived from: Fatāwā Razawiyyaĥ, vol. 8, pp. 243; Baĥār-e-Sharī’at, vol. 1, pp. 740, 741)
When does one become a traveller?
The mere intention of travelling does not render a person traveller. In fact, the rulings of a Shar’ī traveller will apply after he has travelled beyond the populated areas of his town, i.e. his village or city. For a city-dweller to travel beyond the populated suburbs adjacent to his city is also essential.
(Durr-e-Mukhtār, Rad-dul-Muḥtār, vol. 2, pp. 722)