1 Corinthians 6: 9-10:

"Know ye not that the unrighteous shall not inherit the kingdom of God? Be not deceived: neither fornicators, nor idolaters, nor adulterers, nor effeminate (malakoi), nor abusers of themselves with mankind (arsenokoitē), Nor thieves, nor covetous, nor drunkards, nor revilers, nor extortioners, shall inherit the kingdom of God."

1 Timothy 1:9-10:

Knowing this, that the law is not made for a righteous man, but for the lawless and disobedient, for the ungodly and for sinners, for unholy and profane, for murderers of fathers and murderers of mothers, for manslayers, For whoremongers, for them that defile themselves with mankind (arsenokoitēs), for menstealers (slave traders), for liars, for perjured persons, and if there be any other thing that is contrary to sound doctrine."

Arsenokoites (ἀρσενοκοίτης). Said to be a compound word made up by Paul taken from the Septuagint (LXX) reading of Leviticus 20:13 (ἄῤῥην/ἄρσην [arrhēn/arsēn] and κοίτην [koitēn].

'Malakoi' believed to be a passive homosexual with 'arsenokoites' believed to be the aggressive homosexual by so-named "Bible Conservatives." If one word goes with the other to emphasis both sides of a gay relationship, why is 'malakoi' left out of 1 Timothy? If 'arsenokoite' is the catch-all word to mean all homosexuality, why is 'malakoi' used in 1 Corinthians? "Koites" was used centuries before Paul's usage and when used as a suffix in compounds it always indicated the penetrative aggressor, never the passive. That means it can not apply to both partners in a sexual act and cannot be a general term for all homosexual activity.

What we see with Paul, as read by "conservative" exegetes, is the stereotypical "one has to be the female" supposition of a homosexual coupling by anti-gay proponents who believe all homosexual couplings must mimic the male penetrating the female paradigm of a heterosexual coupling. This bares no semblance to most current homosexual relationships. In other words, IF Paul had aggressive males with passive males in mind when writing 1 Corinthians, it can only be applied to Paul's Roman contemporaries who were free men past a certain age in Roman society who strictly played the role of aggressive male (penetrator) with those beneath him in Roman societal standing.

Also, If Paul meant to convey a condemnation of all homosexuality to the audience who were at the time reading his 1 Corinthian and 1 Timothy letters, they would have not gotten that meaning from what he wrote in those passages. Outside of those two Biblical instances of that word, no other written source links the word with homosexuality outside of exploitation, pederasty or an economic injustice. The people reading Paul would have understood the word in those contexts. Paul indeed had access to words to convey a passive and the aggressive homosexual (Greek slang; kinaidhos/kolombaras) or even a catch-all word for an adult homosexual male (androkoitēs), including several words for lesbianism (completely absent in any word form), with what were popular and understood words of his day with homosexuality, but he leaves those terms out in all his writings that would have left no question to his reading audience what he meant.

Another mystery is if Paul wanted to condemn homosexuals in Corinthians and Timothy, why did he feel he had to reach to the Jewish Code, a holiness code that he says is a curse to us (Romans 6:14, 7:6, 2 Cor 3:6, Galatians 2:21, 3:23-25, 5:14) that's also silent on lesbianism to do it? Even if Paul used Leviticus to condemn homosexuality with compounding words,* the Levitical passage he uses is only concerned with anal penetrative sex according to the Rabbinical understanding of the verse (note; The Hebrew expression mishkav zakhar was a term not found in any ancient writing prior to Paul, so to say Paul went with a term coined by the latter Rabbinic is false). 

Sibylline Oracle 2.70-77 (the earliest use of 'arsenokoitai' apart from Paul from a pagan source) lists it within it's injustices category and not in it's sexual category; "Do not steal seeds... Do not arsenokoitein, do not betray information..." Acts of John places it with economic injustices; "...robber, defrauder, arsenokoitai, thief..."

Arsen is placed with economic injustices by Theophiles of Antioch in his treatise addressed to Autolychus.

, in the Attic form arrenokoitas, was found on an inscription of a gate leading to the city of Thessaloniki (Greek Anthology 9.686.5.):

"...barbaron ou tromeeis, ouk arrenas arrenokoitas" ("you need not dread the barbarian nor the male arrenokoitai." Public kidnappers for the purpose of trafficking (shanghaied) is more of a realistic placement here than "male homosexual" since homosexual practice was not forbidden in Thessaloniki.

1 Timothy patterned the last half of his sin list on the Decologue (the last 6 Commandments of the 10 Commandments). Timothy extended his adultery prohibition to include "boy raping" with arsenokoitai, a common practice in Christian sin lists that pattern themselves on the Decologue. The specified "raping of boys," not male/male sex, was an extension of the 7th commandment along with; "Do not have sex with married women," "Do not have sex with prostitutes." The Didache and The Epistle of Barnabas used the word arsenokoitai to replace "boy raper" as an extension of; "Do not commit adultery." A word trick popular at the time with Christian sin lists commenting on adultery.

The word is used to show a powerful aggressor raping a weaker. Some Bibles get it right with translating arsenokoitai as "boy rapers." (Jerusalem Bible, German 1968, "child molesters." "Dutch NBG translation of 1951, "knapenschenders" ("boy-molesters").

In the Apology of Aristides 13, Fragmenta 12, 9-13.5.4, 'arsenokoitai' refers to Zeus abducting and raping a boy named Ganymede. Another occurrence is in Hippolitus Refutatio chapter 5. Where Nass, a Satanic being, is said to have had Adam sexually "like a boy." Babylonian Talmud, b. Sanhedrin 54a puts arsenos koiten in the context of only boy sex. Maimonides on the verse states it's about: 'child corrupting' (Moses Maimonides "The Guide for the Perplexed" p. 376). In Babylonian Talmud Nid-dah 13b it talks about "sporting with children," an explicit reference to pederasty.

* "If a man [ish] lies with a male [zakhar] as with a woman, both of them have committed an abomination (Lev 29:13)."
A distinction is meant between the two types of different males in the verse [Man called an 'ish,' followed by the male he is not to lie down with, a Male called a 'zakhur'] with not putting ish with ish (man/man) or zakhur with zakhur (male/male). 
 The only distinction between Jewish males would be age (note; 'Zakan' is "beard" denoting age, 'Zakayn' is "elder" in Hebrew that might give insight into the 'Zakhar' of Lev 29:13) or one having a religious distinction from the other. Not excluded from this are priestly males (Assinu/Qadesh) in the land of Canaan who hold a function in religious idolatry prohibited to Jewish males who's cult practices involved homosexuality in the service of Moloch worship.

Conclusion: Paul would not have used 'arsenekoitai' to convey a condemnation of homosexuality with the absence of female homosexuality or condemn male homosexuality beyond the Levitical prohibition of anal sex that in all likelihood took place within the idolatry practices of the Canaanites. It looks like the word conveys an exploitive, probable pederastic action with or without idolatry.