“Aren’t the Biblical rules on sex outdated and bigoted?”
God designed sex and he designed it to be pleasurable. But he also designed it for marriage. And he designed marriage for one man and one woman for life. In a heterosexual, committed, monogamous, consensual, marital relationship sex is blessed by God and everything goes.
Outside of Biblical marriage, sex is sin because it violates God’s design and it dehumanizes those who engage in it.
Those that oppose the Biblical design of marriage do so because they refuse to submit to to God’s authority. They serve their own appetites and glorify their own natural passions. But God wants them to repent and glorify him and honor themselves with self restraint.
“Flee fornication. Every sin that a man does is outside of the body; but he that commits fornication sins against his own body. Your body is the temple of the Holy Spirit. Glorify God with your body.” – 1 Corinthians 6:18-20