No prayer should be offered in the presence of food or when he is resisting the need to relieve himself of the two filths
‘Ā’ishah (may Allah be pleased with her) reported: I heard the Messenger of Allah (may Allah's peace and blessings be upon him) say:
"No prayer should be offered in the presence of food or when he is resisting the need to relieve himself of the two filths."
«لَا صَلَاةَ بِحَضْرَةِ الطَّعَامِ، وَلَا هُوَ يُدَافِعُهُ الْأَخْبَثَانِ».
The Messenger of Allah (may Allah's peace and blessings be upon him) forbade praying in the presence of food, which the praying person craves and wants very much. Also, he forbade praying while resisting the need to relieve oneself of the two filths - urine and stool - for this causes distraction.
...:
Before commencing the prayer, a worshiper should eliminate anything that may distract him during their prayer.
Sahīh Muslim (1/ 393) (560).
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شرح النووي على مسلم (5/ 46).
تيسير العلام شرح عمدة الأحكام.
للبسام (ص96).
تنبيه الأفهام شرح عمدة الأحكام.
لابن عثيمين (1/ 123).