I can hear my neighbors having sex.

[barnumandbailey]

They’re at it again.

[Richmondbread]

They’re at it again.

blast a minister at them preaching about eternal hellfire for the sin of fornication.

[Roy]

They’re at it again.

Are they porn-like loud or just audible?

[Mans not hot]

The walls in our apartment building are very thin. Do you suppose I should knock on their door and ask to join?

No! Do not disturb.

[barnumandbailey]

blast a minister at them preaching about eternal hellfire for the sin of fornication.

This is an A1 reaction. Will try next time.

Are they porn-like loud or just audible?

Porn-like. It’s quite comical, actually.

[Richmondbread]

If they aren't married it shouldn't be legal.

[Anglo-Celtic]

If they aren't married it shouldn't be legal.

You're right. The fornicators should be stoned in the town square, right next to the shamed adulterers and masturbators.

[lei.talk]

...if only to hear the neighbors' reaction.

Spoiler!