"Do they then seek the judgement of (the days of) ignorance? And who is better in judgement than Allah for a people who have firm faith?" [Al-Qur'an 5:50]
Allah criticizes those who ignore His commandments which include every type of righteous good thing and prohibit every type of evil, but they refer instead to opinions, desires and customs that people themselves invented, all of which have no basis in His religion. During the time of Jahiliyyah, the people used to abide by the misguidance and ignorance that they invented by sheer opinion and lusts. The Tatar (Mongols) abided by the law that they inherited from their king Genghis Khan who wrote Al-Yasiq for them. This book contains some rulings that were derived from various religions, such as Judaism, Christianity and Islam. Many of these rulings were derived from his own opinion and desires. Later on, these rulings became the followed law among his children, preferring them to the Law of the Book of Allah and the Sunnah of His Messenger, sallallahu 'alayhi wa sallam. Therefore, whoever does this, he is a disbeliever who deserves to be fought against, until he reverts to Allah's and His Messenger's decisions, so that no law, minor or major, is referred to except by His Law. Allah said:Purchase this book"Do they then seek the judgement of (the days of) ignorance?"
Meaning, they desire and want this and ignore Allah's Judgement."And who is better in judgement than Allah for a people who have firm faith?"
Who is more just in decision than Allah for those who comprehend Allah's Law, believe in Him, who are certain that Allah is the best among those who give decisions and that He is more merciful with His creation than the mother with her own child? Allah has perfect knowledge of everything, is able to do all things, and He is just in all matters.
Al-Hafidh Abu'l-Qasim at-Tabarani recorded that Ibn 'Abbas said that the Messenger of Allah, sallallahu 'alayhi wa sallam, said:"The most hated person to Allah is the Muslim who seeks the ways of the days of ignorance and he who seeks to shed the blood of a person without justification." [At-Tabarani 10:374]
Al-Bukhari recorded Abu'l-Yaman narrating a similar hadith with some addition. [Fath al-Bari 12:219]
(s) Tafsir Ibn Kathir (Abridged), Volume 3, Darussalam.