Narrated `Abdullah bin Amir that his father had told him that he had seen the Prophet (p.b.u.h) praying Nawafil at night on the back of his Mount on a journey, facing whatever direction it took.
Related hadith on this topic
Explanation & Benefits
Maulana Dawood Raz
Hadith Commentary:
From this, it is established that the Prophet sallallahu alayhi wa sallam performed voluntary (nafl) prayers while traveling, and it also proves the forenoon (duha) prayer. If it is established that the Prophet sallallahu alayhi wa sallam performed any act even once in his lifetime, that too is Sunnah for the Ummah, and for the forenoon (duha) prayer, there is even more evidence available.
Lady Umm Hani radi Allahu anha has only reported what she herself witnessed.
It is evident that Lady Umm Hani did not have the opportunity to observe all of the Prophet’s sallallahu alayhi wa sallam regular practices at all times.
Source: Sahih Bukhari: Commentary by Maulana Dawood Raz, Page: 1104
Maulana Dawood Raz
Hadith Commentary:
It is established that voluntary (nafl) prayers are permissible while riding, and likewise, the witr prayer as well. This is the view of Imam Shafi'i, Imam Malik, Imam Ahmad, and the Ahl al-Hadith. However, according to Imam Abu Hanifah rahimahullah, it is not permissible to perform the witr prayer while riding.
Source: Sahih Bukhari: Commentary by Maulana Dawood Raz, Page: 1093