(19) You shall observe My statutes (chukotai). You shall not mate your cattle with a different species (kilayim); you shall not sow your field with two kinds of seed (kilayim); you shall not put on clothing from a mixture of two kinds of material (kilayim sha'atnez).
(9) You shall not sow your vineyard with a second kind of seed (kilayim), else the crop—from the seed you have sown—and the yield of the vineyard may not be used. (10) You shall not plow with an ox and an donkey together. (11) You shall not wear sha'atnez - cloth combining wool and linen.
You shall observe my statutes (chukotai) — Such as: “You shall not mate your cattle with a different species, etc.” For חוקים (chukim) are decrees of the King for which no reason for the thing.
(א) את חקותי תשמרו -
רק החקים הם גזירת המלך אשר יחוק במלכותו בלי שיגלה תועלתם לעם... אבל כולם בטעם נכון ותועלת שלימה
והטעם בכלאים כי השם ברא המינים בעולם בכל בעלי הנפשות בצמחים ובבעלי נפש התנועה ונתן בהם כח התולדה שיתקיימו המינים בהם לעד כל זמן שירצה הוא יתברך בקיום העולם וצוה בכחם שיוציאו למיניהם ולא ישתנו לעד לעולם שנאמר בכולם "למינהו" (בראשית א)
והמרכיב שני מינין משנה ומכחיש במעשה בראשית כאילו יחשוב שלא השלים הקב"ה בעולמו כל הצורך ויחפוץ הוא לעזור בבריאתו של עולם להוסיף בו בריות
You shall observe my statutes (chukotai)
...Rather, chukim are like the decrees of a king who decrees it with his authority without revealing their purpose to the people... But all of God's laws have a correct reason and a perfect purpose.
And the reason for kilayim is that God created species in the world - in everything with a soul, in plants, and in everything that moves - and gave them the ability to reproduce, such that the species survive with them forever, so long as the Blessed God wants the world to exist. So God commanded that they be able to produce according to their species, and that they never ever change. As it says, when describing all of them, "according to its species" (Gen. 1)...
And one who crosses two species together, changes and denies the work of Creation, as if they are thinking that the Holy Blessed One did not perfect the world completely, and this person wants to help with God's creation of the world by adding creatures to it.
(א) כִּלְאֵי הַכֶּרֶם אֲסוּרִין מִלִּזְרֹעַ, וּמִלְּקַיֵּם, וַאֲסוּרִין בַּהֲנָאָה. כִּלְאֵי זְרָעִים, אֲסוּרִים מִלִּזְרֹעַ וּמִלְּקַיֵּם, וּמֻתָּרִין בַּאֲכִילָה, וְכָל שֶׁכֵּן בַּהֲנָאָה. כִּלְאֵי בְגָדִים מֻתָּרִין בְּכָל דָּבָר, וְאֵינָן אֲסוּרִין אֶלָּא מִלִּלְבֹּשׁ. כִּלְאֵי בְהֵמָה מֻתָּרִים לְגַדֵּל וּלְקַיֵּם, וְאֵינָן אֲסוּרִים אֶלָּא מִלְּהַרְבִּיעַ.
Kilayim of the vineyard: it is forbidden both to sow and to allow to grow, and it is forbidden to derive benefit from them. Kilayim of seeds: it is forbidden both to sow and to allow to grow, but it is permitted to eat them, and all the more so to derive benefit from them. Kilayim of clothing: is permitted in all respects, except that it is forbidden to wear them. Kilayim of beasts: it is permitted to raise and to keep, and it is only prohibited to cross-breed them.
רַבִּי יְהוּדָה אוֹמֵר, כָּל הַנּוֹלָדִים מִן הַסּוּס, אַף עַל פִּי שֶׁאֲבִיהֶן חֲמוֹר, מֻתָּרִין זֶה עִם זֶה. וְכֵן הַנּוֹלָדִים מִן הַחֲמוֹר, אַף עַל פִּי שֶׁאֲבִיהֶם סוּס, מֻתָּרִין זֶה עִם זֶה. אֲבָל הַנּוֹלָדִים מִן הַסּוּס עִם הַנּוֹלָדִים מֵחֲמוֹר, אֲסוּרִים זֶה עִם זֶה:
Rabbi Yehudah says: all those born from horses, even though their father is a donkey, are permitted one with another. Likewise, all those born from donkeys, even though their father is a horse, are permitted one with another. But those born from a horse with those born from donkeys are prohibited one with another.
הַפְּרוּטִיּוֹת אֲסוּרוֹת, וְהָרַמָּךְ מֻתָּר. וְאַדְנֵי הַשָּׂדֶה, חַיָּה. רַבִּי יוֹסֵי אוֹמֵר, מְטַמְּאוֹת בָּאֹהֶל כָּאָדָם. הַקֻּפָּד וְחֻלְדַּת הַסְּנָיִים, חַיָּה. חֻלְדַּת הַסְּנָיִים, רַבִּי יוֹסֵי אוֹמֵר, בֵּית שַׁמַּאי אוֹמְרִים, מְטַמֵּא כַזַּיִת בְּמַשָּׂא, וְכָעֲדָשָׁה בְּמַגָּע:
Mules of uncertain parentage are forbidden to one another, but a ramakh is permitted. The Masters of the Field are considered a chayah. Rabbi Yossi says: and they cause impurity in a tent like a human being. The hedgehog and the bush-mole are considered a chayah. As for the bush-mole: Rabbi Yossi says in the name of Bet Shammai: an olive's size of its carcass renders a person carrying it unclean, and a lentil’s size of its carcass renders a person touching it unclean.
ואדני השדה - בר נש דטור. נ"ל דר"ל וואלדמענש הנקרא אוראנגאוטאנג והוא מין קוף גדול בקומת וצורת אדם ממש.
The Masters of the Field - that is, men of the field. And it seems to me that this is about the valdmensch called the urangautang, which is a kind of giant monkey, with a height and shape very much like a person.
אדני השדה. חיה הגדלה בשדות, וכמין חבל גדול יוצא מן הארץ שגדלה בו אותה חיה, ושמה ידוע, והוא ידעוני הכתוב בתורה, ומחובר בטבורו באותו חבל היוצא מן הארץ, וצורתו צורת אדם בפרצוף וידים ורגלים ואין כל בריה רשאה לקרב אליו כי הוא הורג וטורף כל הקרב אליו. וכשרוצים לצוד אותו מורים בחצים בחבל עד שנפסק וצועק בקול מר ומת מיד.
The Masters of the Field - This is a wild animal that grows in the fields, that has a kind of big cord coming out of a root in the earth from where it gets its nourishment. And it is also called the Yadua, for is the Yidoni written of in the Torah. It is joined from its navel to that cord coming out of the ground, and it appears human in form, in its facial features, arms and legs. And no creature should approach within the length of that cord, for it it tears and kills everything that comes close. When people want to hunt it, they shoot arrows from afar at its cord until it is severed, and then it screams out a bitter cry, and dies immediately.