ʿUyūn akhbār al-Riḍā
Hadith 129129 - وَبِهذَا الإِسنادِ عَنْ عَلِىِّ بْنِ أَبِي طالِبٍ عَلَيْهِالسَّلامُ قالَ: عَلَيْكُمْ بِاللَّحمِ، فَإِنَّهُ يُنبِتُ اللَّحْمَ، وَمَن تَرَكَ اللَّحْمَ أَرْبَعِينَ يَوْماً ساءَ خُلقَهُ.
31-129 According to the same documentation, Ali ibn Abi Talib (a.s.) said, “I advise you to eat meat since it will strengthen your muscles. Whoever abstains from eating meat for forty days will get bad-tempered.”