This is mentioned in the Bible 1 Corinthians 11:1-16.
Something about the hierarchy of things;
God -> Man -> Woman
How Men should not have long hair or their heads covered while praying but instead have their hair short and shown. Women should not have short hair while praying and instead have long hair.
While I do see the whole hierarchy thing being a product of his time, I am curious as to where he gets this idea of hairstyles from. Is it still practised today with any relevancy to Paul's writings? Was he influenced by his surrounding culture? Was it said by a prophet before him?
I only discovered this while studying his contributions to Christianity and this caught my eye. Also please tell me if I have asked the question incorrectly or if there is another subreddit that could help.
/r/academicbiblical may also be able to help
Let's start with the men. Long hair is can be Jewish, in the context of a Nazarite Vow:
You must not cut his hair throughout the time of his vow of consecration. He must be holy until the time is completed during which he consecrates himself to the Lord; he is to let the hair of his head grow long. (Number 6:5)
But the issue is that long hair, by the 1st century, is heavily associated with paganism or Hellenism. Quoting Tim O'Neill:
This is particularly hard because of the masses of evidence that the first followers of the Jesus sect were devout Jews - a group for whom the idea of adopting anything "pagan" would have been utterly horrific. These were people who cut their hair short because long hair was associated with pagan, Hellenistic culture or who shunned gymnasia and theatres because of their association with pagan culture. All the evidence actually shows that the earliest Jesus sect went through a tumultuous period in its first years trying to accommodate non-Jews into their devoutly Jewish group.
But you'll also find some dissenting opinions on this in the FAQ. I suspect, if nothing else, Paul sought to differentiate masculinity and femininity, which he emphasizes in 11:7-9.
For more on the Hellenization of the Jews, see the following:
You can also look up the Maccabean rebellion, the Samaritans post-exile, and the Alexandrian/ Seleucid/ Ptolemaic kingdoms. I have sources I can dig up for you, if you're interested, but you'll have to give me a few days.
For the women:
Again, this may be Paul simply using a secondary sexual feature to distinguish femininity from masculinity, but I think there's something else clanking around under the hood, so to speak, because of verse 10:
It is for this reason that a woman ought to have authority over her own head, because of the angels.
I have no doubt that this is Paul accepting the so-called "Second Fall of the Angels," that is, that angels came down to earth, had intercourse with women who birthed the Nephilim, and led humankind to destruction in the Noachian Flood. I talk about this here, about halfway down the post.
It is my contention that Paul's "because of the angels" is suggesting that women should not tempt the angels. He keeps prattling on about how women were made for men, not angels, which is a big theme in 1 Enoch when the angels are being sentenced.
And, I just looked up bible commentaries on this verse to shore up my position, and surprisingly Ellicott agrees with me. He does couch his position in more doubt than I do, though.
Is it practiced today? You betcha. Just ctrl+f "corinth." It'll take ya right there.