Ibn Mu’adh on Niyyah: Sincerity distinguishes good and bad deeds

Abu Hayyan reported: Ibn Mu’adh, may Allah have mercy on him, said, “Sincerity distinguishes good deeds from sins, just as milk is distinguished from filth and blood.”

And Sa’id ibn Jubayr, may Allah have mercy on him, said, “Sincerity is to not associate partners with Allah in one’s religion, and to not display ostentation in good deeds to anyone.”

Source: al-Baḥr al-Muḥīṭ 2:139

عن ابن حيان قَالَ ابْنُ مُعَاذٍ رحمه الله الْإِخْلَاصُ تَمْيِيزُ الْعَمَلِ مِنَ الذُّنُوبِ كَتَمْيِيزِ اللَّبَنِ مِنْ بَيْنِ الْفَرْثِ وَالدَّمِ

وَقَالَ سَعِيدُ بْنُ جُبَيْرٍ رحمه الله الْإِخْلَاصُ أَنْ لَا يُشْرِكَ فِي دِينِهِ وَلَا يُرَائِي فِي عَمَلِهِ أَحَدًا

2:139 البحر المحيط