وَمَا أَنْزَلْنَا عَلَيْكَ الْكِتَابَ إِلَّا لِتُبَيِّنَ لَهُمُ الَّذِي اخْتَلَفُوا فِيهِ وَهُدًى وَرَحْمَةً لِقَوْمٍ يُؤْمِنُونَ ﴿۶۴﴾ وَاللَّهُ أَنْزَلَ مِنَ السَّمَاءِ مَاءً فَأَحْيَا بِهِ الْأَرْضَ بَعْدَ مَوْتِهَا إِنَّ فِي ذَلِكَ لَآيَةً لِقَوْمٍ يَسْمَعُونَ ﴿۶۵﴾ وَإِنَّ لَكُمْ فِي الْأَنْعَامِ لَعِبْرَةً نُسْقِيكُمْ مِمَّا فِي بُطُونِهِ مِنْ بَيْنِ فَرْثٍ وَدَمٍ لَبَنًا خَالِصًا سَائِغًا لِلشَّارِبِينَ ﴿۶۶﴾

﴾64﴿ Wa maaa anzalnaa 'alaikal Kitaaba illaa litubaiyina lahumul lazikh talafoo feehi wa hudanw wa rahmatal liqawminy yu'minoon
﴾65﴿ Wallaahu anzala minas samaaa'i maaa'an fa ahyaa bihil arda ba'da mawtihaa; inna fee zaalika la aayatal liqaw miny yasma'oon
﴾66﴿ Wa inna lakum fil an'aami la'ibrah; nusqeekum mimmmaa fee butoonihee mim baini farsinw wa damil labanann khaalisan saaa'ighallish shaaribeen

﴾64﴿ And We have not sent down the Book (the Quran) to you except so that you may explain to them the matters in which they differ, and as a guidance and mercy for a people who believe
﴾65﴿ And Allah, the Most High, sends down water from above, then revives the earth with it after its dryness. Indeed, in this is a great sign for people who listen
﴾66﴿ And indeed, there is a lesson for you in the cattle: We give you to drink from what is in their bellies—between excretion and blood—pure milk, palatable to those who drink it

[64] Since condolences to the Messenger were mentioned in the previous verse, this verse encourages the Messenger of Allah Most High to propagate the Quran.
The meaning of "الَّذِي اخْتَلَفُوا فِيهِ" ("that wherein they differ") refers to matters such as Tawhid (Oneness of Allah), resurrection after death, and other related issues. This verse indicates that disputed matters are resolved through the Quran.
[65] From this verse up to verse (78) is the fourth chapter. In this chapter, six rational arguments are presented, mentioning the creation of beneficial things—such as food, drink, women, and children.
In verse (65), rainwater and plants are mentioned.
In verse (66), milk is mentioned.
In verse (67), juices and beverages are mentioned.
In verse (68), honey is mentioned.
In verse (70), the creation of souls is mentioned.
In verse (72), the creation of women and children is mentioned.
Again, in verse (71), there is an example provided to refute polytheism.
Verse (73) again refutes polytheism in worship.
In verse (74), benefits from various forms of polytheism are mentioned.
Again, two examples to refute polytheism are presented in verses (74, 75).
Verse (77) includes a warning about the Hereafter. In this verse, the word "يَسْمَعُونَ" ("they hear") is mentioned, indicating that at this point, seeing is not essential—hearing alone is sufficient. That is, rain falling and plants flourishing are not everywhere visible, but hearing about it is sufficient.
[66] This rational argument refers to the blessing of milk. The meaning of "بَيْنِ فَرْثٍ وَدَمٍ" ("between excrement and blood") is that a portion of the consumed plant food goes into the stomach and becomes excrement (فرث), while another portion is turned into blood, and from this blood, milk is produced.
The second point is that when food reaches the stomach, it forms layers: excrement (فرث) at the bottom, milk in the middle, and blood above it. Through the liver, blood moves into the veins, milk goes into the udder, and excrement remains in the stomach.
Note: In this verse, the pronoun "بُطُونِهِ" ("their bellies") is masculine, whereas in verse (21) of Surah Mu'minun, the pronoun used is feminine. Here, it interprets the plural collectively as singular due to focusing on just one benefit from cattle. In Surah Mu'minun, the feminine plural pronoun is used because multiple benefits are described. Thus, here the pronoun is singular due to mentioning only one benefit, while in Surah Mu'minun, the plural form is preferred due to numerous benefits.