Mishkat al-Masabih 21 Foods كتاب الأطعمة 46

وَعَن سلمانَ قَالَ: قَرَأْتُ فِي التَّوْرَاةِ أَنَّ بَرَكَةَ الطَّعَامِ الْوُضُوءُ بَعْدَهُ فَذَكَرْتُ ذَلِكَ لِلنَّبِيِّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ فَقَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: «بَرَكَةُ الطَّعَامِ الْوُضُوءُ قَبْلَهُ وَالْوُضُوءُ بعدَه» . رَوَاهُ التِّرْمِذِيّ وَأَبُو دَاوُد

Salman said he read in the Torah that the blessing of food consists in ablution after it, and when he mentioned that to the Prophet he said, “The blessing of food consists in ablution before it and ablution after it.” Tirmidhi and Abu Dawud transmitted it.