S2
Milk "from between digested food and blood"
16:66 points to an ordinary drink and calls it "a lesson": "pure milk, palatable to drinkers", which comes "between excretion and blood".
وَإِنَّ لَكُمْ فِى ٱلْأَنْعَٰمِ لَعِبْرَةً ۖ نُّسْقِيكُم مِّمَّا فِى بُطُونِهِۦ مِنۢ بَيْنِ فَرْثٍ وَدَمٍ لَّبَنًا خَالِصًا سَآئِغًا لِّلشَّٰرِبِينَ٦٦
Transliteration: wa-inna lakum fī l-anʿāmi laʿib'ratan nus'qīkum mimmā fī buṭūnihi min bayni farthin wadamin labanan khāliṣan sāighan lilshāribīna
And indeed, for you in grazing livestock is a lesson. We give you drink from what is in their bellies - between excretion and blood - pure milk, palatable to drinkers.
Translation: Saheeh International
Key words
ʿIbra ("lesson") is something you cross over from: you look at one thing and pass to understanding another. Farth ("excretion") is the contents of the gut; dam is blood; labanan khāliṣan is "pure milk"; sāʾighan means easy to swallow.
"Their bellies"
The Arabic pronoun is singular (buṭūnihi, "its bellies"), although it refers to plural livestock; commentators discussed this (below).
Setting
Sura al-Naḥl ("The Bee") is Meccan. This verse is one of a run of signs of God's provision: rain (16:65), milk (16:66), fruits of the palm and the vine (16:67), and the bee (16:68–69).
Classical tafsir
Ibn Kathir. "A lesson" means "a sign and an evidence of the wisdom, power, mercy and kindness of the Creator". On the singular pronoun: it "refers to one cattle, or it could refer to the whole species". On how the milk arises, he describes separation "after the food has been fully digested in its stomach", after which "the milk goes to the udder".
Al-Jalālayn. "between the refuse the intestinal waste and the blood pure milk uncontaminated by either the refuse or the blood".
What they share. Both read the verse as about purity: milk comes from among things no one would drink, yet nothing of either is in it. Ibn Kathir's sentence about digestion is the closest either comes to physiology, and it is a general description, not an anatomy.
How it works
Each point below is tied to the verse's phrase "between excretion and blood".
- From food to blood. Established Digested food is absorbed from the gut into the blood. Milk's raw materials come out of the digestive tract and travel in the blood.
- From blood to milk. Established Cornell's guide: "Milk synthesis takes place in the alveoli", tiny sacs in the udder lined with milk-making cells. These cells take what they need from the blood: long-chain fatty acids are "absorbed from the blood" (short-chain ones are made in the gland), and "Milk protein is synthesized from amino acids also with origin from the blood". Milk is not filtered blood; the cells build new substances (milk sugar, milk proteins, milk fat) from what the blood brings.
- How much blood. Established (as an average) "To produce 1 liter of milk 500 ltr. of blood have to pass through the udder" (Cornell). The figure is an average used in dairy science; it varies with the cow and her yield.
Points of awe
Milk sugar, milk protein and much of milk fat are made new inside the udder's alveoli, from materials in the blood (Cornell).
Reflection
The verse could have said simply, "We give you milk." Instead it slows down and names where milk comes from: "between excretion and blood". Those are two things people turn away from. And out of them, the verse says, comes "pure milk, palatable to drinkers" (16:66).
The commentators heard a lesson about purity. Al-Jalālayn says the milk is "uncontaminated by either the refuse or the blood"; Ibn Kathir calls the whole process "a sign and an evidence" of the Creator's wisdom and kindness. The verse itself calls it ʿibra, a lesson you cross over: from the glass in your hand to the One who made it possible.
There is also a lesson a reader can take inward, as a reflection rather than a reading of the verse. What is clean and good does not always come from clean and easy places. It often comes from what was mixed and difficult, when it has passed through the right process. That is true of many good lives.
The verse sits in a passage about rain, fruit and honey. Each is ordinary. Each, the sura says, is provision. The fitting response is the one the Quran asks for again and again: to notice, and to be grateful.
Questions readers ask next
Does the verse describe milk production scientifically?
No. It is an image of purity coming from between impurities. The physiology is described separately, with its limits, in "How it works".
Why does it say "its bellies" and elsewhere "their bellies"?
Ibn Kathir says the singular pronoun can refer to one animal or to the whole species.
Is milk really made from blood?
Its raw materials come from the blood, but milk is not blood. Cells in the udder build milk sugar, protein and fat from what the blood brings (Cornell).
What is the "lesson" (ʿibra)?
For Ibn Kathir, a sign of the Creator's "wisdom, power, mercy and kindness". The verse invites the reader to pass from the drink to the Giver.
Sources
- Saheeh International — 16:66.
- Ibn Kathir, Tafsir (abridged English), and Tafsīr al-Jalālayn (English), on 16:66, https://surahquran.com/tafsir-english-aya-66-sora-16.html.
- "Anatomy of the Mammary Gland", Cornell University (adapted from DeLaval material) — blood volume per litre of milk; how milk components are made, as read.
- "The Formation of Milk", by Truth Seeker Staff, "Taken with slight editorial modifications from Miracles of the Qur'an website", islam.com.kw, https://www.islam.com.kw/?p=30907 — the popular modern claim.
- CSIRO Publishing (2005)
- Cornell University, on blood flow through the mammary gland
- Ibn Kathīr and al-Qurṭubī on 16:66