Halakhah su Levitico 20:23

We are not permitted to follow the ways of the gentiles, nor adopt their styles in dress or in hair style or similar things, as it is said: "You shall not follow the ways of the gentile."³Leviticus 20:33. It is [also] said: "In their ways you shall not follow"⁴Leviticus 18:3. It is [also] said: "Guard yourself lest you be ensnared to follow them."⁵Deuteronomy 12:30. You should not wear a garment which is specifically worn by them as a symbol of ostentation, such as a garment of high-ranking officers. For example, the Talmud states:⁶Maseches Sanhedrin 74a. that it is forbidden for a Jew to be similar to them even in regard to shoelaces; if their practice was to tie one way and the practice of Jews to tie another way, or if their practice was to wear red shoelaces and Jews wear black shoelaces because the color black indicates humility, submissiveness and modesty. [In all such instances] it is forbidden for a Jew to deviate. From these examples everyone should learn how to apply these standards to his time and place. A garment designed for showiness or immodesty must not be worn by a Jew, but rather his clothing should be made in a style which suggests humility and modesty. The following is mentioned in Sifrei: You should not say that since they go out with scarlet I shall go out with scarlet, since they go out with kulsin (the word kulsin meaning weaponry) I also shall go out with kulsin, because these practices are indicative of arrogance and haughtiness which are not the heritage of Jacob. Rather, our heritage demands of us to be modest and humble, and not be influenced by the haughty. Similarly, any custom or statute of which there is a suspicion of idolatrous intent or background should be avoided by Jews. Similarly, you should not cut your hair or style your hair as they do, but rather you should be distinct, in your clothing and speech and all other endeavors just as you are distinct in your perspectives and concepts. Similarly, it is said: "I have set you apart from the nations."⁷Leviticus 20:26.

And the negative commandment of this prohibition was repeated in its stating, "and you shall not do from any of [these] abominations" (Leviticus 18:26), which includes all of these matters which are an abomination to God, may He be blessed. [This] means to say, that one who does them distances himself from the good and removes from himself the providence of God, blessed be He. And this is the understanding of the abominable to the Lord, may He be blessed, in every place, according to that which I have heard. And also that which is written at the end of the matter, "for all of these abominations did the people of the land that were before you do" (Leviticus 18:27), "and I was disgusted with them" (Leviticus 20:23). And the matter is to say that the trait is very disgusting. And every thing that is bad and very vile, Scripture describes as if God, may He be blessed, hates. And it is all according to the matter that we said; and similar to what they, may their memory be blessed, said in every place (Mekhilta d'Rabbi Yishmael 19:18:2), [it is] in order to break [to assuage] the ear to that which it can hear. And the language of Sifra, Achrei Mot, Section 8:8 is "'Like the deed of the land of Egypt and like the deed of the land of Canaan, etc.' (Leviticus 18:27) - perhaps they should not build or plant as they do? [Hence] we learn to say, 'and in their statutes you shall not walk.' I have only said those statutes which were instituted for them, and not their buildings. What did they do? A man would wed a man, and a woman, a woman; and a woman would wed two men."

To not follow the practices of the gentiles: To not follow the practices of the Amorites and so [too,] the practices of the gentiles, as it is stated (Leviticus 20:23), "And you shall not follow the practice of the nation that I am driving out before you." And the law is the same for all the nations, since the matter is that they turn away from [following] God, and worship idolatry. And the content of the commandment is that we not behave like them in our clothing and our matters. And it is like they said in Sifra, Achrei Mot, Chapter 13:8, "'And do not follow their practices - that you not follow their mores with things that are fixed for them, such as theaters, circuses and amphitheaters" - and all of these are types of frivolity that they would do in their gatherings, when they gathered to do craziness, licentiousness and idolatry. And they said there, "'The practice of the nation' - Rabbi Meir says, 'These are the ways of the Amorites that the sages numbered (see Shabbat 67a).' Rabbi Yehudah ben Betira says, 'That you should not grow a tassel of the head and not cut its growth'" - meaning to say that he not shave from the sides and leave hair in the middle, which is called a forelock. And this negative commandment is repeated in another place with other words, as it is stated (Deuteronomy 12:30), "Guard yourself lest you be ensnared to follow them." And the language of Sifrei is "'Guard' is with a negative commandment; 'lest' is with a negative commandment; 'you be ensnared to follow them' is lest you imitate them and do like their deeds; 'and it shall be a snare for you' is that you not say, 'Since they go out with velvet, I will go out with velvet, since they go with helmets, I will go with a helmet'" - and that is a type of knight's armor. And the language of the books of prophecy (Zephaniah 1:8) is "and upon all of the dressed, there is a foreign dress."