O ye who believe! make not unlawful the good things which Allah hath made lawful for you, but commit no excess: for Allah loveth not those given to excess.
The second principle is that Islam has restricted the authority to legislate the haram and the halal, taking it out of the hands of human beings, regardless of their religious or worldly position, and reserving it for the Lord of human beings alone. Neither rabbis nor priests, kings or sultans, have the right to prohibit something permanently to Allah’s servants; if someone does this, he has certainly exceeded his limits, usurping the sovereignty which, with respect to legislating for the people, belongs to Allah Subhanahu wa Ta’ala alone. Others who acquiesce with this transgression of such usurpers and act upon what they have legislated thereby elevate them to the rank of partners or associates with Allah: Do they have partners (with Allah) who have prescribed for them in religion that concerning which Allah has given no permission? (42:21)
They have taken their rabbis and priests as lords besides Allah, and the Messiah, son of Mary, although they were commanded to worship no one except the One Allah. There is no Deity but He, glory be to Him above what they associate with Him! (9:31)
The Qur’an took to task the People of the Book, that is, Christians and Jews, for putting the power to make lawful and to prohibit things and actions into the hands of their rabbis and priests.
‘Adi bin Hatim, who had been a Christian before accepting Islam, once came to the Prophet (peace be on him). When he heard him reciting the above ayah he said, “O Messenger of Allah, but they do not worship them.” The Prophet (peace be on him) replied, Yes, but they prohibit to the people what is halal and permit them what is haram, and the people obey them. This is indeed their worship of them. (Reported and classified as hasan by al-Tirmidhi and others.)
Christians still claim that Jesus (peace be on him), before ascending to heaven, vested in His apostles the authority to declare things permissible or prohibited as they saw fit, as reported in Matthew 18:18:
I tell you this: whatever you forbid on earth shallbe forbidden in heaven, and whatever you allow on earth shall be allowed in heaven.
The Qur’an also took the pto task for legislating and prohibiting things without any authority from Allah: Do you see what Allah has sent down to you for sustenance and yet you have made some part of it halal and some part haram?(10:59)
And do not say, concerning the falsehood which your tongues utter, ‘This is halal and that is haram,’ in order to fabricate a lie against Allah; assuredly those who fabricate a lie against Allah will not prosper. (16:116)
From these explicit verses of the Qur’an and from clear ahadith of the Prophet (peace be on him), the jurists of Islam grasped with certainty that it is Allah Subhanahu wa Ta’ala alone Who has the right to make lawful or to prohibit a matter, either through His Book or through the tongue of His Messenger (peace be on him). The jurists’ task does not go beyond explaining what Allah has decreed to be halal or haram “when He has explained to you in detail what He has made haram for you.” (6:119) It is definitely not their task to decide what is to be allowed and what is to be prohibited to human beings. Thus the great jurists, in spite of their scholarship and ability of ijtihad (deduction from analogy), shied away from pronouncing judgements concerning matters of halal and haram, passing the problem from one to the other out of fear of committing the error of declaring halal what is actually haram and vice-versa.
In his book Al-Umm, Imam Shafi’i narrated that Abu Yusuf, a companion of Abu Hanifah and a chief judge (qadi), said:
I know that our knowledgeable teachers avoided saying, ‘This is halal and that is haram,’ apart from what they found clearly stated without requiring an interpretation in the Book of Allah. We have been told by Ibn al-Saib that al-Rabi’ bin Khaytham, one of the greatest of the second generation Muslims, said, ‘Beware that none of you says, “Allah has made this lawful or approves of it,” and that Allah may then say that He did not make it lawful nor approve it, or that you say, “Allah has prohibited this,” and that Allah may then say, “You lie! I did not prohibit it nor disapprove of it.” Some companions of Ibrahim alNakh’i, a great jurist of Kufah among the second generation Muslims, have told us of his mentioning his colleagues as saying, when they gave a judgement concerning something, ‘It is disapproved’ or ‘There is no harm in it,’ rather than, ‘It is haram’ or ‘It is halal,’ as haram and halal are terms of much greater import. (AI-Umm, vol. 7, p. 317.)
This is what Abu Yusuf has reported concerning our righteous forebearers and what al-Shafi’i has quoted from him, in agreement with his position. Similarly, Ibn Muflih reported the great scholar Ibn Taymiyyah, as saying that the jurists of the early days of Islam did not term anything haram unless it was definitely known to be so. (This is further supported by the fact that the companions did not give up the drinking of alcohol after the revelation of the Qur’anic verse, “They ask thee concerning wine and gambling. Say: In them is great sin and some benefit,” (2:219) since this verse did not definitely prohibit drinking prior to the revelation of the verses in Surah al-Maida. (5:93-94 (90-91)) In the same spirit, the great imam Ahmad ibn Hanbal, when asked about some matter, would say, “I disapprove of it” or “It does not appeal to me,” or “I do not like it” or “I do not prefer it.” Similar reports are narrated concerning Malik, Abu Hanifah, and all the other imams (may Allah be pleased with them). (This is a lesson to the followers of such imams who freely use the word “haram’ without having a proof, or even a semblance of proof.)
Al-Qaradawi, Yusuf (1960). The Lawful and Prohibited in Islam. (p. 11). http://www.islamicweblibrary.com/wp-content/uploads/2019/06/TheLawfulAndTheProhibitedInIslamal-halalWalHaramFilIslamByShaykhYusufAlQardawi.pdf