(11) CHAPTER. Whoever did not offer the Nawafil (optional - non-obligatory) before and after the (compulsory) Salat (prayer) during a journey.
Narrated Hafs bin `Asim: Ibn `Umar went on a journey and said, I accompanied the Prophet and he did not offer optional prayers during the journey, and Allah says: 'Verily! In Allah's Apostle you have a good example to follow.' (33.21)
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