Does walking invalidate the Adhan or Iqamah?
Chapter on Adhan
Al-Mughni
Book of Prayer
Primary text
If the Mu'adhin neglects facing the Qibla or walks while performing the Adhan, the Adhan is not voided. The Khutbah (sermon) is considered more emphatic than the Adhan and is not invalidated by these actions. Regarding walking during the Adhan, Ahmad stated that the command concerning the Adhan is easy. Regarding the Iqamah, Ahmad preferred that the Mu'adhin complete the recitation before walking.
Supporting text
For a traveler, Ahmad preferred that the Adhan be called while facing the Qibla, though he hoped it would suffice if not done.