Al-Kāfi - Volume 1 > Chapter on Those who use their Knowledge to Fill their Stomach and are Boastful for it
Hadith #6

6 ـ مُحَمَّدُ بْنُ إِسْمَاعِيلَ عَنِ الْفَضْلِ بْنِ شَاذَانَ عَنْ حَمَّادِ بْنِ عِيسَى عَنْ رِبْعِيِّ بْنِ عَبْدِ الله عَمَّنْ حَدَّثَهُ عَنْ ابي جعفر (عَلَيْهِ السَّلام) قَالَ مَنْ طَلَبَ الْعِلْمَ لِيُبَاهِيَ بِهِ الْعُلَمَاءَ أَوْ يُمَارِيَ بِهِ السُّفَهَاءَ أَوْ يَصْرِفَ بِهِ وُجُوهَ النَّاسِ إِلَيْهِ فَلْيَتَبَوَّأْ مَقْعَدَهُ مِنَ النَّارِ إِنَّ الرِّئَاسَةَ لا تَصْلُحُ إِلا لاهْلِهَا.

6. Muhammad ibn ’Isma‘il has narrated from al-Fadl ibn Shadhan from Hammed ibn ‘Isa from Ri’ab‘i ibn ‘Abdallah from one he narrated from abu Ja’far (a.s.) who has said the following. “Whoever would seek knowledge to show off to the scholars or to engage in arguments with fools or to attract people to himself he should know that in so doing he has prepare his seat in the fire. Leadership does not suite anyone besides those qualified for it.”