Your question: “Why does the bible say that you shouldn't judge people or that Jesus loves everyone but homosexuality is a sin?”
The Bible does not say anything. It is a book, not an audio emitter. The correct way to pose such a question would be, “Why is there a directive in the Bible against judging others, a claim that Jesus loves everyone, and that homosexuality is a sin?”
You will see later in this post why that is an important point when we get to "the living word" schema below.
Suppose you are serious, which is probably not the case, but the answer is as follows.
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It is clear that you have not actually read the Bible and do not know the cultural and historical context in which the stories were written. Those contexts vary according to period and place. I do not suggest that you should read the Bible. It is religious propaganda, has no secret meaning known only to Bible scholars, and overall is a great waste of time.
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In order:
The injunction against homosexuality is from the Old Testament and is in regard to laws imposed on the Hebrews by their government. That would be Moses and his thugs, although it is alleged that some sole and unique creator god, Yahweh, transmitted the laws to Moses who then imposed the laws on his followers. Those who succeeded Moses (professional priests, mainly, as a caste among Hebrews) supposedly have kept a written record of the laws as part of the Torah.
How much is myth and how much has a connection to history cannot be discerned from the Bible because the Bible appears to be overwhelmingly myth, with some mention of ancient cities, kings, and ethnic groups. Any text, in fact, that claims some god transmitted laws to some person to impose on others cannot be accurate, including the Quran. That is because as far as anyone can demonstrate, there is no god.
See:
• https://en.wikipedia.org/wiki/Law_of_Moses
and
"Homosexuality--What Does the Bible Teach?"
• http://www.middletownbiblechurch.org/prelatio/prelat9.htm
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Why the anti-homosexuality law was instituted is not clear, but it may have been to make sure that Hebrews reproduced frequently and did not have waste their time seeking erotic thrills while the Hebrews were attempting to displace other ethnic groups during their alleged search for the Promised Land.
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More from you: “So my friends are mildly Christian.”
The term “So” is used before a conclusion, a premise. You can drop it from your sentence and thus appear to be able to communicate in written English with some expertise rather than just inserting words for no reason.
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More of your claims: “They all support or does not care about gay marriage. They said it doesn't make sense. If Jesus loves everyone as long as you don't hurt anyone else, and that it says you should not judge your neighbors(peers), why does it say homosexuality is a sin? That's saying you shouldn't judge people while saying you can judge people by who they love, and saying that Jesus loves everyone that isn't harmful but he hates people based on who they would rather love. I don't get how the puzzle pieces come together.”
For Bible-thumpers, it does make sense. Not Christians are obsessed with the Bible and many have not even read the Bible. Those who are obsessed with the Bible believe it to be what they refer to as the living word of God, meaning that some god will direct their attention to the correct part of the Bible by which to make moral decisions. The same god, they claim, reveals to them how some passage should guide their moral code in particular situations.
Similar problems occur among Muslims who frequently believe the Quran is the absolute moral authority of some sole and unique creator god, Allah, and that whatever directives appear in the Quran are directives that ought to be followed by all believers everywhere.
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Jesus is a very minor player in the Bible, appearing in only four short chapters of the New Testament, all of which were propaganda written on a common theme, the story of Jesus of Nazareth, none of which has been authenticated. The Gospels were written long after Jesus would have been dead.
Christians are not bound to obey directives from the figure Jesus in the Bible. Claims and directives attributed to Jesus were meant for a particular class of persons at a particular time and place.
The only qualification for being a Christian is to seriously believe there exists some sole and unique god, Jesus, who according to Jesus himself is his own father. Allegedly the Christian God was originally Yahweh (or any of a few other names for the same god). But that god reproduced with a mortal woman, Mary, sometimes referred to as the Mother of God. The latter title came about because their offspring, Jesus, who after performing miracles and doing some faith healing seminars revealed to his close followers that he and his father were the same. The rest is not history, either, so I will cut the story short here.
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Jesus is a personal god, i.e., believers claim that they have a personal relationship with Jesus who knows their secret thoughts and who is always available for consultation, typically by injecting thoughts into their mind in response to prayer and/or sending personalized messages in otherwise ordinary events that have secret meaning known only to Jesus and the believer.
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The point is that Christians might believe anything. For example:
"My feelings as a Christian points me to my Lord and Savior as a fighter. It points me to the man who once in loneliness, surrounded by a few followers, recognized these Jews for what they were and summoned men to fight against them and who, God’s truth! was greatest not as a sufferer but as a fighter. In boundless love as a Christian and as a man I read through the passage which tells us how the Lord at last rose in His might and seized the scourge to drive out of the Temple the brood of vipers and adders. How terrific was His fight for the world against the Jewish poison."
- Adolf Hitler, in a speech on 12 April 1922 (Norman H. Baynes, ed. The Speeches of Adolf Hitler, April 1922-August 1939, Vol. 1 of 2, pp. 19-20, Oxford University Press, 1942)
• http://www.nobeliefs.com/hitler.htm
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Compare that to the Mormon dogma:
"I believe the Book of Mormon was delivered by the angel Moroni to our holy prophet Joseph Smith in 1827, engraved in the lost language of reformed Egyptian on golden plates. I believe our holy prophet Joseph Smith translated the Book of Mormon into English and returned the original to Moroni.
"I believe the Book of Mormon accurately depicts events in ancient North America between 2200 BC to 421 AD, wherein a lost tribe of Hebrews who had migrated there built a great civilization that subsequently declined due to war that broke out between two factions.
"I believe that Native Americans are the descendants of one of those factions, the other faction having been annihilated. I believe that our Lord and Savior Jesus Christ appeared to those indigenous peoples of North America.
"I believe that by believing all of the above and otherwise following in the traditions of the Church of Jesus Christ of the Latter Day Saints that I personally will live forever in Heaven after I die.
"And you will not, you ungrateful heathens."