user7792: "Homosexuality" is a hot topic everywhere in the world now. But is it a sin according to Buddhism? Does it cause a breaking of the third precept? I have heard in a sermon that people are born gay because of breaking the third precept severely in previous births and people are born as females for also breaking the third precept (not as severely I suppose). I know that where I come from if the government accepts gay marriages the monks will be the first to protest even before the church does! Is it because it is a sin? 
(PS: I am totally fine with someone being gay)

user7611: Monks were expelled for homosexual activity, both heterosexual and homosexual activity is not allowed for monks and nuns.
So it is considered as sinful or harmful.

"At that time the venerable Upananda, of the Sakya tribe, had two
  novices, Kandaka and Mahaka; these committed sodomy with each other.
  The Bhikkhus were annoyed, &c.: 'How can novices abandon themselves to
  such bad conduct?'
They told this thing to the Lord Buddha, &c.
'Let no one, O Bhikkhus(Monks), ordain two novices. He who does, is
  guilty of a dukkata offence.'" - (Mahavogga, 1.52)

Homosexuals aren't allowed to be monks, neither are those who practice heterosexual activity.

"Now, what is the taking on of a practice that is pleasant in the
  present but yields pain in the future? There are some brahmans &
  contemplatives who hold to a doctrine, a view like this: 'There is no
  harm in sensual pleasures.' Thus they meet with their downfall through
  sensual pleasures. They consort with women wanderers who wear their
  hair coiled in a topknot.
"The thought occurs to them: 'Now what future danger concerning
  sensual pleasures do those [other] brahmans & contemplatives foresee
  that they have spoken of the relinquishment of sensual pleasures and
  describe the full comprehension of sensual pleasures? It's pleasant,
  the touch of this woman wanderer's soft, tender, downy arm.'" -
  Cula-dhammasamadana Sutta


user8586: Shashank, There is no such thing as "sin" in Buddhism. Karma, yes, but not sin. Although, it is a rule for monks to avoid sexual relations, it does not apply to the laity. However, it seems to me that meditation will diminish sexual appetite regardless of monk or lay person. In the mean time, it is good to control sexual desire as there is a proper place, a proper time, and proper partner. It is kind of vague what the last one means, but at least it forbids adultery. As for being genetic, the latest and most extensive scientific studies I have seen suggest that homosexuality is NOT genetic.   

user8157: The Pali suttas are silent on the matter of homosexuality. The matter of homosexuality is only mentioned in the monk's Vinaya, where certain types of ex-homosexuals (but not all) are forbidden from ordaining as a monk.  
Further, homosexuality does not fall into the definition of 'sexual misconduct', which essentially is having sex with individuals who are in existing relationships (such as having sex with another person's husband or wife or with a child/teenager still living in the care of their parents). 
It follows homosexuality itself is not a 'sin' or 'transgression' in original Buddhism. 

user10732: I can not comment, so I will post here.
"Miccha dhamma" is never about homosexuality. The comment of the Cakkavattisuttaṃ (DN 26) is wrong.
The word "miccha dhamma" and other two words are also appear in the Palokasuttaṃ (AN.3.56), and no comment about homosexuality here (as far as I know).
Obviously, "miccha dhamma" just means any wrong doctrines or something away from sammā (involving greed to others' belongings or possessions) which happening in natural and man-made disasters, not some specific action.
The three words (adhamma-rāga), (visama-lobha), (miccha dhamma) have the similar meaning. The meaning of rāga is similar to lobha, and the meaning of visama is similar to adhamma & miccha dhamma. So, it does not mean some specific action, and the three words are just some ancient pali collocations.
That wrong comment just came from some medieval homophobic buddhists like any homophobic Buddhists in the Modern times, whether he is living in Sri Lanka or not, whether where he living colonized by Britain's CHRISTIAN CUSTOM or not.
Non-majority is not deviant practice, as left-handers are not. However discrimination against minority is deviant practice, so anyone does so is deviant.
And I must say if homosexuality involving any of this, then Buddha would say more in other suttas, not just appearing in the mouth of some medieval homophobic commentators and their homophobic followers.
The comment of Palokasuttaṃ (AN.3.56) also mentioned (adhamma-rāga), (visama-lobha), (miccha dhamma), but it does not mention anything about homosexuality. You can see：" Micchādhammaparetāti avatthupaṭisevanasaṅkhātena micchādhammena samannāgatā. Devo na sammā dhāraṃ anuppavecchatīti vassitabbayutte kāle vassaṃ na vassati. Dubbhikkhanti dullabhabhikkhaṃ. "
Another Buddhism scripture《大薩遮尼乾子所說經》（Bodhisattvagocaropāyaviṣayavikurvāṇanirdeśa) also mentioned  that the miccha dhamma is about learning Tirthika's doctrine.  (於諸外道非義論中起義論想。於無益論生利益想。於非法中生是法想。於末世時。非是智者所作論中。以為正論。生於信心。熏修邪見。以為福德。是名邪法羅網纏心)
This [Tirthika's doctrine] is the correct meaning of the DA 26 "Miccha dhamma", not the ridiculous, discriminative explanation and its bigot speaker.
The Counterfeit of the True Dhamma（SN 16.13） said：「when a counterfeit of the true Dhamma arises in the world, then the true Dhamma disappears.」.
Those homophobic followers let a counterfeit of the true Dhamma arises, as they wrongly explain DA 26.

user295: 1st of all Buddhism does not prohibit or have anything against being gay. But Hethorosexuality is unwholsome as it is rooted in desire, though lay people may engage in such activities, within Sila. Homosexuality activity needs to have stronger attraction than is Hethorosexual avtivity, which is more unwholsome. When engaging in any sexsual activity if compaired to a fall, Hetrosexuality say is a 3 foot fall, hence you get hurt in the long run less, Homosexuality is a 6 foot fall, which you you are likely to get more hurt by this in the long run than Hethorosexuality, as weight of attaction is stronger between partners. Incest is more grave like say a 9 foot fall. There will be future society when this also may become accepted, according to the quote below. In each case the attachment is relative. Also historically hetrosexsual people have been less liberal, but current liberal practices have more attachment than in the past so more unwholesome mind moments.
Any form of sexual attraction including being gay is based on desire which is unwholesome and result experiences which are painful in the future. Buddhism deals with correcting your mental tendencies by getting rid of the roots which creates misery. This is done through practicing Vipassana and is a gradual process. Through Vipassana you can transcend any sexual preferences and orientation. To get more insights into this it is best you take a course at: https://www.dhamma.org or http://www.internationalmeditationcentre.org/
See: Saññoga Sutta

According to the Dīgha Commentary, here “abnormal lust” (adhamma,raga) refers to incest, that is,
“lust between mother and mother’s sister and father’s sister and maternal uncle’s wife and other such
improper situations” (mata matuccha pituccha matulanī ti adike ayutta-t,thane rago); “neurotic desire”
(visama,lobha) refers to excessive greed by way of consuming things (paribhoga,yuttesu pi thanesu atibalava,lobho,
in other words, excessive materialism and consumerism); and “deviant practices” (miccha,dhamma)
refer to sexuality “between men and men, women with women.” (DA 3:853)

Homosexuality is a deviant practice (miccha,dhamma). This is rooted in excessive lust.

Now, bhikshus, amongst those humans whose life-span was 500 years, three things were widespread,
that is, abnormal lust, excessive desire and deviant conduct.
With the increase of abnormal lust, excessive desire and deviant conduct,
the life-span of beings declined, their beauty declined, too.
For these humans whose life-span and beauty were declining, whose lifespan was 500 years, that of some of their children was 250 years, and some 200 years.

More lust in deviant practices is worse off that non deviant pratice like hetrosexuality, which in some cases in the past may have been less rooted in desire, but both are rooted in unwholesomeness.
See: Cakka,vatti Siha,nāda Sutta
Sin is violation of God's will or religious ideal. In Buddhism there is no concept of God's will but with respect to ideal we can consider anything creating unwholesome fabrications as a sin then it will be. Sila general deals with more stronger Karma with can influence rebirth. In this context it is not clear cut but still in contravention of the religious ideal as homosexuality is considered a deviant practice.

user7049: it's not a sin for the simple reason that a concept of sin is alien to the Dhamma, if anything it would be an unskillful, impure act
on the basis of sexual misconduct description from the Nikayas it's impossible to construe that being homosexual or engaging in homosexual sex per se is a violation of the precept

He engages in sensual misconduct. He gets sexually involved with those who are protected by their mothers, their fathers, their brothers, their sisters, their relatives, or their Dhamma; those with husbands, those who entail punishments, or even those crowned with flowers by another man. 

Cunda sutta (AN 10.176) but it's a stock passage found elsewhere across the four NIkayas

user7909: I'm shocked at some of the responses here - to try to twist the precepts of Buddhism to condemn something that one finds personally abhorrent is counter to everything The Buddha taught.
Yes, allowing lust to dominate your thoughts is counter to the path of enlightenment but the question was that of homosexuality - not sex. Those that are quick to condemn homosexuality are perhaps tainted by cultural or prior religious indoctrination and should look at heterosexual practices that seem to be accepted all too readily.
I have never seen anything in Buddhist teachings that forbids a man to find companionship with another man or likewise between two women. 
I would suggest that as long as any relationship is based upon loving kindness and continual compassion towards the other person, it is not forbidden. 
Of course I could be wrong. :)

user-1: It is not a sin.
Lust is born out of desire. Desire is one of the root defilements (kilesas).
It can manifest itself in different ways, e.g. sexual preference, body type preferences etc.
Lust is still lust, no matter what object its involved with.

7792: <p>"Homosexuality" is a hot topic everywhere in the world now. But is it a sin according to Buddhism? Does it cause a breaking of the third precept? I have heard in a sermon that people are born gay because of breaking the third precept severely in previous births and people are born as females for also breaking the third precept (not as severely I suppose). I know that where I come from if the government accepts gay marriages the monks will be the first to protest even before the church does! Is it because it is a sin? 
(PS: I am totally fine with someone being gay)</p>
 7611: <p>Monks were expelled for homosexual activity, both heterosexual and homosexual activity is not allowed for monks and nuns.</p>

<p>So it is considered as sinful or harmful.</p>

<blockquote>
  <p>"At that time the venerable Upananda, of the Sakya tribe, had two
  novices, Kandaka and Mahaka; these committed sodomy with each other.
  The Bhikkhus were annoyed, &amp;c.: 'How can novices abandon themselves to
  such bad conduct?'</p>
  
  <p>They told this thing to the Lord Buddha, &amp;c.</p>
  
  <p>'Let no one, O Bhikkhus(Monks), ordain two novices. He who does, is
  guilty of a dukkata offence.'" - (Mahavogga, 1.52)</p>
</blockquote>

<p>Homosexuals aren't allowed to be monks, neither are those who practice heterosexual activity.</p>

<blockquote>
  <p>"Now, what is the taking on of a practice that is pleasant in the
  present but yields pain in the future? There are some brahmans &amp;
  contemplatives who hold to a doctrine, a view like this: 'There is no
  harm in sensual pleasures.' Thus they meet with their downfall through
  sensual pleasures. They consort with women wanderers who wear their
  hair coiled in a topknot.</p>
  
  <p>"The thought occurs to them: 'Now what future danger concerning
  sensual pleasures do those [other] brahmans &amp; contemplatives foresee
  that they have spoken of the relinquishment of sensual pleasures and
  describe the full comprehension of sensual pleasures? It's pleasant,
  the touch of this woman wanderer's soft, tender, downy arm.'" -
  Cula-dhammasamadana Sutta</p>
</blockquote>
 8586: <p>Shashank, There is no such thing as "sin" in Buddhism. Karma, yes, but not sin. Although, it is a rule for monks to avoid sexual relations, it does not apply to the laity. However, it seems to me that meditation will diminish sexual appetite regardless of monk or lay person. In the mean time, it is good to control sexual desire as there is a proper place, a proper time, and proper partner. It is kind of vague what the last one means, but at least it forbids adultery. As for being genetic, the latest and most extensive scientific studies I have seen suggest that homosexuality is NOT genetic.   </p>
 8157: <p>The Pali suttas are silent on the matter of homosexuality. The matter of homosexuality is only mentioned in the monk's Vinaya, where certain types of ex-homosexuals (but not all) are forbidden from ordaining as a monk.  </p>

<p>Further, homosexuality does not fall into the definition of 'sexual misconduct', which essentially is having sex with individuals who are in existing relationships (such as having sex with another person's husband or wife or with a child/teenager still living in the care of their parents). </p>

<p>It follows homosexuality itself is not a 'sin' or 'transgression' in original Buddhism. </p>
 10732: <p>I can not comment, so I will post here.</p>

<p>"Miccha dhamma" is never about homosexuality. The comment of the Cakkavattisuttaṃ (DN 26) is wrong.</p>

<p>The word "miccha dhamma" and other two words are also appear in the Palokasuttaṃ (AN.3.56), and no comment about homosexuality here (as far as I know).</p>

<p>Obviously, "miccha dhamma" just means any wrong doctrines or something away from sammā (involving greed to others' belongings or possessions) which happening in natural and man-made disasters, not some specific action.</p>

<p>The three words (adhamma-rāga), (visama-lobha), (miccha dhamma) have the similar meaning. The meaning of rāga is similar to lobha, and the meaning of visama is similar to adhamma &amp; miccha dhamma. So, it does not mean some specific action, and the three words are just some ancient pali collocations.</p>

<p>That wrong comment just came from some medieval homophobic buddhists like any homophobic Buddhists in the Modern times, whether he is living in Sri Lanka or not, whether where he living colonized by Britain's CHRISTIAN CUSTOM or not.</p>

<p>Non-majority is not deviant practice, as left-handers are not. However discrimination against minority is deviant practice, so anyone does so is deviant.</p>

<p>And I must say if homosexuality involving any of this, then Buddha would say more in other suttas, not just appearing in the mouth of some medieval homophobic commentators and their homophobic followers.</p>

<p>The comment of Palokasuttaṃ (AN.3.56) also mentioned (adhamma-rāga), (visama-lobha), (miccha dhamma), but it does not mention anything about homosexuality. You can see：" Micchādhammaparetāti avatthupaṭisevanasaṅkhātena micchādhammena samannāgatā. Devo na sammā dhāraṃ anuppavecchatīti vassitabbayutte kāle vassaṃ na vassati. Dubbhikkhanti dullabhabhikkhaṃ. "</p>

<p>Another Buddhism scripture《大薩遮尼乾子所說經》（Bodhisattvagocaropāyaviṣayavikurvāṇanirdeśa) also mentioned  that the miccha dhamma is about learning Tirthika's doctrine.  (於諸外道非義論中起義論想。於無益論生利益想。於非法中生是法想。於末世時。非是智者所作論中。以為正論。生於信心。熏修邪見。以為福德。是名邪法羅網纏心)</p>

<p>This [Tirthika's doctrine] is the correct meaning of the DA 26 "Miccha dhamma", not the ridiculous, discriminative explanation and its bigot speaker.</p>

<p>The Counterfeit of the True Dhamma（SN 16.13） said：「when a counterfeit of the true Dhamma arises in the world, then the true Dhamma disappears.」.</p>

<p>Those homophobic followers let a counterfeit of the true Dhamma arises, as they wrongly explain DA 26.</p>
 295: <p>1st of all Buddhism does not prohibit or have anything against being gay. But Hethorosexuality is unwholsome as it is rooted in desire, though lay people may engage in such activities, within Sila. Homosexuality activity needs to have stronger attraction than is Hethorosexual avtivity, which is more unwholsome. When engaging in any sexsual activity if compaired to a fall, Hetrosexuality say is a 3 foot fall, hence you get hurt in the long run less, Homosexuality is a 6 foot fall, which you you are likely to get more hurt by this in the long run than Hethorosexuality, as weight of attaction is stronger between partners. Incest is more grave like say a 9 foot fall. There will be future society when this also may become accepted, according to the quote below. In each case the attachment is relative. Also historically hetrosexsual people have been less liberal, but current liberal practices have more attachment than in the past so more unwholesome mind moments.</p>
<p>Any form of sexual attraction including being gay is based on desire which is unwholesome and result experiences which are painful in the future. Buddhism deals with correcting your mental tendencies by getting rid of the roots which creates misery. This is done through practicing Vipassana and is a gradual process. Through Vipassana you can transcend any sexual preferences and orientation. To get more insights into this it is best you take a course at: <a href="https://www.dhamma.org" rel="nofollow noreferrer">https://www.dhamma.org</a> or <a href="http://www.internationalmeditationcentre.org/" rel="nofollow noreferrer">http://www.internationalmeditationcentre.org/</a></p>
<p>See: <a href="http://www.themindingcentre.org/dharmafarer/wp-content/uploads/2009/12/8.7-Sannoga-S-a7.48-piya.pdf" rel="nofollow noreferrer">Saññoga Sutta</a></p>
<blockquote>
<p><em><strong>According to the Dīgha Commentary</strong></em>, here “abnormal lust” (adhamma,raga) refers to incest, that is,
“lust between mother and mother’s sister and father’s sister and maternal uncle’s wife and other such
improper situations” (mata matuccha pituccha matulanī ti adike ayutta-t,thane rago); “neurotic desire”
(visama,lobha) refers to excessive greed by way of consuming things (paribhoga,yuttesu pi thanesu atibalava,lobho,
in other words, excessive materialism and consumerism); and <strong>“deviant practices” (miccha,dhamma)
refer to sexuality “between men and men, women with women.”</strong> (DA 3:853)</p>
</blockquote>
<p>Homosexuality is a deviant practice (miccha,dhamma). This is rooted in excessive lust.</p>
<blockquote>
<p>Now, bhikshus, amongst those humans whose life-span was 500 years, three things were widespread,</p>
<p>that is, abnormal lust, excessive desire and deviant conduct.</p>
<p>With the increase of abnormal lust, excessive desire and deviant conduct,</p>
<p>the life-span of beings declined, their beauty declined, too.</p>
<p>For these humans whose life-span and beauty were declining, whose lifespan was 500 years, that of some of their children was 250 years, and some 200 years.</p>
</blockquote>
<p>More lust in deviant practices is worse off that non deviant pratice like hetrosexuality, which in some cases in the past may have been less rooted in desire, but both are rooted in unwholesomeness.</p>
<p>See: <a href="http://www.themindingcentre.org/dharmafarer/wp-content/uploads/2010/02/36.10-Cakkavatti-Sihanada-S-d26-piya.pdf" rel="nofollow noreferrer">Cakka,vatti Siha,nāda Sutta</a></p>
<p>Sin is violation of God's will or religious ideal. In Buddhism there is no concept of God's will but with respect to ideal we can consider anything creating unwholesome fabrications as a sin then it will be. Sila general deals with more stronger Karma with can influence rebirth. In this context it is not clear cut but still in contravention of the religious ideal as homosexuality is considered a deviant practice.</p>
 7049: <p>it's not a sin for the simple reason that a concept of sin is alien to the Dhamma, if anything it would be an unskillful, impure act</p>

<p>on the basis of sexual misconduct description from the Nikayas it's impossible to construe that being homosexual or engaging in homosexual sex per se is a violation of the precept</p>

<blockquote>
  <p>He engages in sensual misconduct. He gets sexually involved with those who are protected by their mothers, their fathers, their brothers, their sisters, their relatives, or their Dhamma; those with husbands, those who entail punishments, or even those crowned with flowers by another man. </p>
</blockquote>

<p><a href="http://Cunda%20Kammaraputta%20Sutta" rel="noreferrer">Cunda sutta (AN 10.176)</a> but it's a stock passage found elsewhere across the four NIkayas</p>
 7909: <p>I'm shocked at some of the responses here - to try to twist the precepts of Buddhism to condemn something that one finds personally abhorrent is counter to everything The Buddha taught.</p>

<p>Yes, allowing lust to dominate your thoughts is counter to the path of enlightenment but the question was that of homosexuality - not sex. Those that are quick to condemn homosexuality are perhaps tainted by cultural or prior religious indoctrination and should look at heterosexual practices that seem to be accepted all too readily.</p>

<p>I have never seen anything in Buddhist teachings that forbids a man to find companionship with another man or likewise between two women. </p>

<p>I would suggest that as long as any relationship is based upon loving kindness and continual compassion towards the other person, it is not forbidden. </p>

<p>Of course I could be wrong. :)</p>
 -1: <p>It is not a sin.</p>

<p>Lust is born out of desire. Desire is one of the root defilements (kilesas).
It can manifest itself in different ways, e.g. sexual preference, body type preferences etc.</p>

<p>Lust is still lust, no matter what object its involved with.</p>
