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 dīn. 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 ﷺ. Therefore, whoever does this, he is a disbeliever
Hudhayfah ibn al-Yaman said: ‘Islam is divided into eight parts. The prayer is one part, zakat is one part, fasting is one part, hajj is one part, ‘umrah is one part, jihad is one part, commanding what is known to be right is one part, and forbidding what is recognised as wrong is one part. Disappointed is he who has no part of Islam.’
That exists now in these times with the internecine wars between Muslims and when the power of the unbelievers has become great and they have taken control of Muslims lands* so that there is only the minimum of Islam left. We ask Allah to grant us His pardon, help and kindness.
From Muhammad, Messenger of Allah, to Jaifar and 'Abd, sons of al-Julanda, and may peace be upon those who follow Allah's guidance. To proceed, I invite you both to Islam; accept Islam and you will attain salvation, for I am Allah's Messenger to all mankind so that I may warn those who are alive and establish (Allah's) word over the unbelievers. If you declare your Islam I will appoint you both as governors [of your lands], but if you refuse then (know that) your dominion is only fleeting, and my horsemen will dismount in your courtyard, and my Prophethood will prevail over your dominion.
“Al-Qurtubi, as well as other scholars, said that this Āyah (2:30) proves the obligation of appointing a Khalīfah to pass judgements on matters of dispute between people, to aid the oppressed against the oppressor, to implement the Islamic penal code and to forbid evil. There are many tasks that can only be fulfilled by appointing the Imam, and what is necessary in performing an obligation, is an obligation itself.” [Tafsir Ibn Kathir, Vol. 1 p. 185]
"and that would be part of the dīn of Allah which is obliged for him, just as every responsible person knows from the dīn of Allah what is obliged for him regarding the five prayers, fasting Ramadan, ḥajj and the like"
“Not everyone is capable of carrying out the actions necessary to enjoin right conduct. However, this can be performed effectively by the ruler [Sultan] because he holds the authority to frame laws that will be in accord with the Shari‘ah. As ruler, he has the final word in matters of consequence, such as the legislation … Continue reading The Role of the Sultan in Enjoining Right and Forbidding Wrong in Tafsir al-Qurtubi
When your Lord said to the angels, ‘I am putting a khalif on the earth,’ they said, ‘Why put on it one who will cause great corruption on it and shed blood when we glorify You with praise and proclaim Your purity?’ He said, ‘I know what you do not know.’ [2:30] ‘I am … Continue reading The Caliphate in Tafsir al-Qurtubi