Paul was being fatherly, apostolic, and authoritative in (NIV) Ephesians 5:
Can married couples joke about sex or does this fall under “coarse jesting” too?
That's up to the husband and the wife.
How about sexual humor in TV shows?
If it bothers your conscience, then don't watch it.
Is a Christian allowed to watch something like “South Park” and enjoy and laugh at the sexual humor found in it, or must we disapprove of it?
I did watch a few episodes of South Park. Later, I found it too much and stopped watching.
How about pedophilia jokes? Rape jokes? Bestiality jokes?
No. No. No. I would not listen to these.
Philippians 4:
1 Follow God’s example, therefore, as dearly loved children.
Focus on the Paraclete of peace dwelling in you. Check your conscience against these things.4 Nor should there be obscenity, foolish talk or coarse joking, which are out of place, but rather thanksgiving.
Can married couples joke about sex or does this fall under “coarse jesting” too?
That's up to the husband and the wife.
How about sexual humor in TV shows?
If it bothers your conscience, then don't watch it.
Is a Christian allowed to watch something like “South Park” and enjoy and laugh at the sexual humor found in it, or must we disapprove of it?
I did watch a few episodes of South Park. Later, I found it too much and stopped watching.
How about pedophilia jokes? Rape jokes? Bestiality jokes?
No. No. No. I would not listen to these.
Philippians 4:
8 Finally, brothers and sisters, whatever is true, whatever is noble, whatever is right, whatever is pure, whatever is lovely, whatever is admirable—if anything is excellent or praiseworthy—think about such things.