What a great question.
Heaven. Maybe sex is heaven for some people. But before we can answer this question we have to step back and clarify the word we’re using, heaven. This infers the Heaven of the Bible. Heaven does not exist in Buddhism, nor does it exist in Hinduism.
In Buddhism (and Hinduism as well) the after-life is Nirvana—not Kurt Cobain’s band but an enlightenment that has to do with the release of rebirth/reincarnation cycle. More accurately, it is a state. It is not a place. To make it more daunting there is a very long process of nirvana and then there is the final nirvana, called the parinirvana. Unfortunately, Buddha did not give any details about the parinirvana. And it’s very difficult for most people to get there. Buddha taught if you followed all of his instructions very carefully you possibly make it. But essentially, it is not something that lies within human conception. It’s quite abstract, like a nothingness. They say it’s “a state of being utterly without wanting.” Many might see this as nihilistic. Regardless, there is no sex to be found here.
In Islam, being like the rebellious off-spring of Judeo-Christianity in the 7th century that it was, is based on Judeo-Christian stories. So for Muslims, heaven exists, and it is a place. In Islamic heaven there are rivers flowing with milk and wine (Surah 47:15). Rivers of wine, mmmm. Time to get drunk off your rocker. The rivers of wine is considered “compensation” for what they did not get to enjoy here on earth because here on earth the Qu’ran forbids alcohol. But what about women? And sex? The Qu’ran does not forbid it, obviously. Muhammad had 11 wives including really young ones—notably the infamous Aisha girl, who was married to Muhammad at age 6 and, apparently, had it consummated by age 9. Muhammed was about 50 years he elder. So there is no need for sex compensation in heaven for Muslims, yet, they get it anyway. And boy do they get it. Surah 52:20 says, “They will be reclining on thrones lined up, and We will marry them to fair women with wide eyes.” The hadith (collection of sayings of Muhammad) point out that each guy will receive 70-100 virgins for wives who will always stay virgins. Young men who die a ‘martyr in jihad‘ (a.k.a. suicide bomber) are guaranteed the promise of paradise—milk, wine, and scores of virgins all to himself. And if virgins aren’t enough, there are servant boys at your disposal too (Surah. 52:24). Clearly, sex is really high on the list of values in Islam, for men at least. If you don’t die a jihad-martyr then you can only hope that you did enough meritorial works here to be granted entrance.
In Judaism, heaven is vague. It is spoken of very little in the Torah (the five books of Moses). Moses was given the ten commandments for living on earth “that it may go well with you” but no clear revelation of the future plan of God. Hebrew prophets spoke of future hope (Jer. 29:11), but go no further. This leaves it a bit of a mystery unless you get into Kabbalistic Judaism (mystical Judaism) then you’ll learn all kinds of mystifying ideas about seven different heavens.
When Jesus appeared and started his movement, Christianity, he spoke in concrete terms of Heaven, calling it “The Kingdom of Heaven” (Matt. 18:3, 19:23, Mark 4:26-29) Jesus has a ton to say about heaven and what it is. The closest he gets to sex is at Matthew 22:30 where he says, “For in the resurrection they neither marry nor are given in marriage, but are like angels in heaven.” Because this is as far as it goes, debate has ensued over what exactly it means and different schools of thought provided by theologians. Some say this means no sex. Some are not so sure. By teaching a ‘resurrection’ Jesus is obviously talking about a down-to-earth like life—heaven being something not so much new as in something re-newed. But a practical down-to-earth consideration of this verse would tell us that Heaven is a do-over of life on this planet, and not a Star-Trek teleportation to some other dimension or planet in space. There is no indication anywhere in the Bible of a complete change of plans from the plan God had at the beginning in Genesis 1 and 2 which shows that God’s plan was to make sexual beings who would enjoy one another and their habitation that they were made for forever. The resurrection as a reboot of the great computer program of creation would mean that the man and woman would be ‘back in the garden’ from which they were banned, naked and unashamed. They will also be physically unhindered by decay and death and work would be as it was intended—easy and pleasurable. There is a more telling clue in that same verse, “like angels in heaven”. Nowhere in the Bible are female angels mentioned. They are all male (Michael, Gabriel, Satan, etc.). So what Jesus was talking about was the fact that angels don’t take wives. This is the context of the verse. But angels can have sex and also procreate. In Genesis 6:2 angels, “sons of God”, took daughters of men and ‘married’ them and then “gave birth” to giant humans. They weren’t supposed to do this and thus apparently ended up in punishment (2 Pet. 2:4, Jud. 1:6). Humans will still be sexual beings (male and female) in the resurrection and capable of procreation, Heaven. So while Heaven may be a ‘reboot’, sex and procreation there are issues absent from the texts. There is also the interesting fact that the inauguration of the Kingdom of God is by a wedding between the Church “Bride” and Christ himself, also called the “marriage supper of the lamb”. Clearly, there is a lot more to this issue than we can comprehend. Sex or no sex, Jesus’ words ultimately lead us to consider Heaven as a place that is far better than sex which is a far cry from the orgies in the Muslim paradise and the sub-par marital sex-lives, one-night stands, and cheap porn of the present life.