Sunan Ibn Majah 616
سنن ابن ماجه#616SahihIt was narrated that 'Abdullah bin Arqam said:"The Messenger of Allah said: 'If anyone of you needs to defecate and the immediate call to prayer (Iqamah) is given, let him start with (relieving himself)
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Al-AlbaniSahih
Muhammad Fouad Abd al-BaqiSahih
Shuaib Al ArnautSahih
Zubair Ali ZaiSahih
In-book reference: 1:350