Amir al-mu’minin said in disparagement of the differences of view among the theologians
ومن كلام له (عليه السلام)
في ذمّ اختلاف العلماء في الفتيا
[وفيه يذم أهل الرأي ويكل أمر الحكم في أمور الدين للقرآن]
When1 a problem is put before anyone of them he passes judgement on it from his imagination. When exactly the same problem is placed before another of them he passes an opposite verdict. Then these judges go to the chief who had appointed them and he confirms all the verdicts, although their Allah is One (and the same), their Prophet is one (and the same), their Book (the Qur’an) is one (and the same)!

تَرِدُ عَلَى أحَدِهِمُ القَضِيَّةُ في حُكْمٍ مِنَ الاْحْكَامِ فَيَحْكُمُ فِيهَا بِرَأْيِهِ، ثُمَّ تَرِدُ تِلْكَ القَضِيَّةُ بِعَيْنِهَا عَلَى غَيْرِهِ فَيَحْكُمُ فِيها بِخِلافِ قَوْلِهِ، ثُمَّ يَجْتَمِعُ القُضَاةُ بِذلِكَ عِنْدَ إمامِهِم الَّذِي اسْتَقْضَاهُم فَيُصَوِّبُ آرَاءَهُمْ جَمِيعاً، وَإِلهُهُمْ وَاحِدٌ! وَنَبِيُّهُمْ وَاحِدٌ! وَكِتَابُهُمْ وَاحِدٌ!
Is it that Allah ordered them to differ and they obeyed Him? Or He prohibited them from it but they disobeyed Him? Or (is it that) Allah sent an incomplete Faith and sought their help to complete it? Or they are His partners in the affairs, so that it is their share of duty to pronounce and He has to agree? Or is it that Allah the Glorified sent a perfect faith but the Prophet fell short of conveying it and handing it over (to the people)? The fact is that Allah the Glorified says:

We have not neglected anything in the Book (Qur’an) . . . (6:38),

and in it is a ‘clarification of everything’2 And He says that one part of the Qur’an verifies another part and that there is no divergence in it as He says:

.And if it had been from any other than Allah, they would surely have found in it much discrepancy. (4:82)

أَفَأَمَرَهُمُ اللهُ ـ سُبْحَانَهُ ـ بِالاخْتلاَفِ فَأَطَاعُوهُ! أَمْ نَهَاهُمْ عَنْهُ فَعَصَوْهُ! أَمْ أَنْزَلَ اللهُ سُبْحَانَهُ دِيناً نَاقِصاً فَاسْتَعَانَ بِهِمْ عَلَى إِتْمَامِهِ! أَمْ كَانُوا شُرَكَاءَ لَهُ فَلَهُمْ أَنْ يَقُولُوا وَعَلَيْهِ أَنْ يَرْضِى؟ أَمْ أَنْزَلَ اللهُ سُبْحَانَهُ دِيناً تَامّاً فَقَصَّرَ الرَّسُولُ (صلى الله عليه وآله) عَنْ تَبْلِيغِهِ وَأَدَائِهِ؟ وَاللهُ سُبْحَانَهُ يَقُولُ: (مَا فَرَّطْنَا في الكِتَابِ مِنْ شَيْء) وَفِيهِ تِبْيَانٌ لِكُلِّ شَيْء، وَذَكَرَ أَنَّ الكِتَابَ يُصَدِّقُ بَعْضُهُ بَعْضاً، وَأَنَّهُ لاَ اخْتِلافَ فِيهِ، فَقَالَ سُبْحَانَهُ: (وَلَوْ كَانَ مِنْ عِنْدِ غَيرِ اللهِ لَوَجَدُوا فِيهِ اخْتِلافاً كَثِيراً)
Certainly the outside of the Qur’an is wonderful and its inside is deep (in meaning). Its wonders will never disappear, its amazements will never pass away and its intricacies cannot be cleared except through itself.

وَإِنَّ القُرآنَ ظَاهِرُهُ أَنِيقٌ وَبَاطِنُهُ عَمِيقٌ، لاَ تَفْنَى عَجَائِبُهُ، وَلاَتَنْقَضِي غَرَائِبُهُ، وَلاَ تُكْشَفُ الظُّلُمَاتُ إلاَّ بِهِ.