وَإِنَّمَا هَلَكَ مَنْ كَانَ قَبْلَكُمْ بِطُولِ آمَالِهِمْ...
It does not behoove one who knows His greatness to assume greatness, but the greatness of those who know His greatness is that they should abase themselves before Him, and the safety for those who know what His power is, lies in submitting to Him. Do not be scared away from the truth like the scaring of the healthy from the scabbed person, or the sound person from the sick.
You should know that you will never know guidance unless you know who has abandoned it, you will never abide by the pledges of the Qur'an unless you know who has broken them, and will never cling to it unless you know who has forsaken it. Seek these things from those who own them because they are the life-spring of knowledge and death of ignorance.
They are the people whose commands will disclose to you their (extent of) knowledge, their silence will disclose their (capacity of) speaking and their outer appearance will disclose their inner self. They do not go against religion, and do not differ from one other about it, while it is among them a truthful witness and a silent speaker.