Al-Kāfi - Volume 7 > Accepting a Bribe for Issuing Judgments
Hadith #2

2- عِدَّةٌ مِنْ أَصْحَابِنَا عَنْ أَحْمَدَ بْنِ مُحَمَّدِ بْنِ عِيسَى عَنِ الْحُسَيْنِ بْنِ سَعِيدٍ عَنْ أَخِيهِ الْحَسَنِ عَنْ زُرْعَةَ عَنْ سَمَاعَةَ عَنْ أَبِي عَبْدِ اللهِ (عَلَيْهِ السَّلام) قَالَ الرِّشَا فِي الْحُكْمِ هُوَ الْكُفْرُ بِاللهِ.

2. A number of our people have narrated from Ahmad ibn Muhammad ibn ‘Isa from al-Husayn ibn Sa‘id from his brother al-Hassan from Zur‘ah from Sama‘ah, who has narrated the following: “Abu ‘Abd Allah, ‘Alayhi al-Salam, has said, ‘Accepting a bribe to issue a judgment is denial of the existence of Allah.’”