In Matthew 22:23-33, the religious teachers called the Sadducees asked Jesus a question concerning the law involving marriage. In response, Jesus stated in verse 30, "For in the resurrection they neither marry nor are given in marriage, but are like angels in heaven." His answer clearly notes that marriage will not take place in heaven. Because sex is designed for marriage, then sex will also not take place in heaven.
Will sex be part of heaven?
People in heaven will be "like angels in heaven." This does not mean people turn into angels, but that people in heaven will likewise exist as beings who focus on worship and service to God.
Further, from God's perspective, sex is a unifying part of the marriage relationship and is not meant for any other relationship. When a person is married, "'Therefore a man shall leave his father and his mother and hold fast to his wife, and the two shall become one flesh'? So they are no longer two but one flesh" (Matthew 19:5-6). This need for oneness as a married couple will no longer be necessary in heaven. The Lord Himself will satisfy every need and desire.
Some argue that sex will take place in heaven because sex is a part of who we are, not what we do. In other words, there will be gender roles of male and female in heaven because that is part of our identity. However, this is distinct from saying people will participate in sexual activities in heaven. There will be no need for these activities if God provides complete contentment and every desire is already satisfied.
People appear to still have a body in heaven, but do not perform the same activities or roles associated with our human bodies on earth. Instead, we will worship God, "And I heard every creature in heaven and on earth and under the earth and in the sea, and all that is in them, saying, 'To him who sits on the throne and to the Lamb be blessing and honor and glory and might forever and ever!'" (Revelation 5:13), feast with the Lord (Isaiah 25:6; Matthew 8:11; Luke 22:30), live together with other believers, celebrate (Revelation 19:9) serve God (Matthew 4:10), and exist in amazing surroundings (Revelation 21—22).
Will marriage exist in heaven?
In heaven, will there be different genders? Is there such a thing as gender in heaven?
Will we know our friends and family members in Heaven?
When we're in heaven will we remember our earthly lives?
What will we be doing in heaven? Won't it get boring if we are there forever?
Truth about Eternity