Should a worshiper in the first row, who feels abdominal pain and flatulence that he can suppress until the end of the prayer, suppress the flatulence and complete his prayer, or release the flatulence and interrupt his prayer?

A person who resists the urge to relieve themselves of the "two impure things" (urine and feces) is called al-Haziq. According to the Shafi'i and Hanbali schools, it is disliked (makruh (definition)) to begin prayer while resisting the urge to relieve oneself of one or both of these impure things. The prayer is valid, though disliked, if one does not relieve oneself, unless the strong urge leads to the omission of a pillar or an obligation. As for the Hanafis, they consider it prohibitively disliked (makruh tahrim) absolutely, whether before or during the prayer, and one must interrupt the prayer if there is no fear of missing the prayer time. The Malikis hold that the prayer is nullified if the person resisting the urge reaches a point where they cannot perform the obligatory parts of the prayer at all or except with extreme difficulty.