﴿ يَٰٓأَهْلَ ٱلْكِتَٰبِ لَا تَغْلُوا۟ فِى دِينِكُمْ وَلَا تَقُولُوا۟ عَلَى ٱللَّهِ إِلَّا ٱلْحَقَّ ۚ إِنَّمَا ٱلْمَسِيحُ عِيسَى ٱبْنُ مَرْيَمَ رَسُولُ ٱللَّهِ وَكَلِمَتُهُۥٓ أَلْقَىٰهَآ إِلَىٰ مَرْيَمَ وَرُوحٌۭ مِّنْهُ ۖ فَـَٔامِنُوا۟ بِٱللَّهِ وَرُسُلِهِۦ ۖ وَلَا تَقُولُوا۟ ثَلَٰثَةٌ ۚ ٱنتَهُوا۟ خَيْرًۭا لَّكُمْ ۚ إِنَّمَا ٱللَّهُ إِلَٰهٌۭ وَٰحِدٌۭ ۖ سُبْحَٰنَهُۥٓ أَن يَكُونَ لَهُۥ وَلَدٌۭ ۘ لَّهُۥ مَا فِى ٱلسَّمَٰوَٰتِ وَمَا فِى ٱلْأَرْضِ ۗ وَكَفَىٰ بِٱللَّهِ وَكِيلًۭا ﴾

“O FOLLOWERS of the Gospel! Do not overstep the bounds [of truth] in your religious beliefs, and do not say of God anything but the truth. The Christ Jesus, son of Mary, was but God's Apostle - [the fulfilment of] His promise which He had conveyed unto Mary - and a soul created by Him. Believe, then, in God and His apostles, and do not say, "[God is] a trinity". Desist [from this assertion] for your own good. God is but One God; utterly remote is He, in His glory, from having a son: unto Him belongs all that is in the heavens and all that is on earth; and none is as worthy of trust as God.”

O People of the Scripture do not go to excess in your religion�That is, do not exceed the limits in your religion through innovations (bidaʿ), or by deviating from the truth, which is the Book, the Sunna and consensus (ijmāʿ), by inclining towards the desire of your lower selves.And he [Sahl] said:The backbone (qiwām) of religion and this world is in three things: knowledge (ʿilm), propriety (adab) and initiative (mubādara). However, the ruin of religion and this world comes from three things: ignorance (jahl), folly (khurq) and laziness (kasal).On another occasion, I heard him say:There are four things which are among the buttresses (daʿāʾim) of the religion: to uphold the truth even against your own self and others; to renounce falsehood in yourself or others; to love the people who are obedient to God and to detest those who disobey Him.He was asked about His words, Exalted is He: