حَدَّثَنَا مُحَمَّدُ بْنُ الْمُصَفَّى الْحِمْصِيُّ، حَدَّثَنَا بَقِيَّةُ، عَنْ حَبِيبِ بْنِ صَالِحٍ، عَنْ أَبِي حَىٍّ الْمُؤَذِّنِ، عَنْ ثَوْبَانَ، عَنْ رَسُولِ اللَّهِ ـ صلى الله عليه وسلم ـ أَنَّهُ قَالَ ‏"‏ لاَ يَقُومُ أَحَدٌ مِنَ الْمُسْلِمِينَ وَهُوَ حَاقِنٌ حَتَّى يَتَخَفَّفَ ‏"‏ ‏.‏

It was narrated from Thawban that: The Messenger of Allah said: "No one among the Muslims should stand to pray when he is suppressing (the need to urinate or defecate), until he has to relieve himself." Translation Not Available

Book Ref: Sunan Ibn Majah Book 1 Hadith 619
Web Ref:  Sunan Ibn Majah Vol 1 Book 1 Hadith 619