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Surah 6. Al-An'am
Ayah 138
138وَقَالُوا۟ هَـٰذِهِۦٓ أَنْعَـٰمٌ وَحَرْثٌ حِجْرٌ لَّا يَطْعَمُهَآ إِلَّا مَن نَّشَآءُ بِزَعْمِهِمْ وَأَنْعَـٰمٌ حُرِّمَتْ ظُهُورُهَا وَأَنْعَـٰمٌ لَّا يَذْكُرُونَ ٱسْمَ ٱللَّهِ عَلَيْهَا ٱفْتِرَآءً عَلَيْهِ ۚ سَيَجْزِيهِم بِمَا كَانُوا۟ يَفْتَرُونَ
[138] They say, these cattle and crops are reserved; only those people can eat them, whom we allow. In fact, this is a restriction they themselves have imposed.111 Then there are some animals which have been forbidden for riding and carrying loads, and there are other animals over which they do not pronounce the name of Allah.112 They have falsely attributed all this to Allah113 before long Allah will recompense them for all that they have falsely attributed to Him.
111Here another self-made religious regulation of the mushrik Arabs has been refuted. They used to make vows to reserve certain cattle or the products of certain fields for some particular temple or saint or deity and had made set rules for their use. Accordingly, the right of the use of different kinds of offerings was reserved for a particular kind of people. Allah has declared these to be acts of shirk and warned them against these self-made laws, as if to say, "We will punish you for making vows concerning offerings to others from provisions provided by Us, because We have neither commanded you to make such vows nor prescribed restrictions for their use. All these things have been invented by the rebellious and arrogant people who shall be dealt with severely."
112We learn from traditions that in certain forms of vows and offerings, it was not considered right to pronounce the name of Allah over cattle. It was also forbidden to ride on them during the Hajj journey, because one has to pronounce: Labbaik, Allahumma labbaik: "I am present, O my Allah, I am present," during it. Likewise, they insisted that Allah's name should not be mentioned while milking them or riding them or slaughtering them or eating them.
113That is, "These regulations were not prescribed by Allah, but they were following these with the conviction that they had been prescribed by Allah. though they had no authority from Allah for this thing. The only authority, they had, was that it had been the practice of their forefathers."