I've got a theory about what is considered coarse language. 
It began one day when I was using a Strong's Concordance of the Bible...
I was intrigued to see these words listed: piss, pisseth, ...
Evidently there was a time, about 200 years ago, when these words were respectable enough to include in a bible translation.
I checked the verse reference, and found that these are references to where David and King Saul have a close encounter in a cave. The words
literally used, if I recall, refer to "cover his feet". This, in the highly idiomatic Hebrew language, can mean several things, such as resting, or performing excretory functions, or having sex. 

This casts new light, by the way, on the story of Ruth, doesn't it? It appears that Ruth staked her rightful claim to Boaz in an act of faith...
The bible is an extremely candid book!

The apostle Paul says, in considering his worldly credentials, that he
considers them all "loss" in comparison to his riches in Christ.
If you check into the literal word used, you find that it could be
"delicately" translated as "manure". It's a "plain", coarse word.

I'd also point out that the conversation between Jesus and the woman at the well is fraught with sexual innuendo. You see, wells are frequently used in proverbs as a sexual metaphor. When Jesus referred to himself as living water, and told her that if she drank that water she would never thirst again, it is very likely, in view of the sexual content of the conversation, that he was humorously "teasing" her, playing on her purient interests, while gently leading her to a realization of her moral condition.

The language of the new testament is not the scholarly
classical greek but a "common" street talk.

There is, according to scripture, a time for everything, including, it
seems from the examples I cite, a time for "common" plain speech.

I wonder if one of the reasons
that more men aren't attracted to religion is that it's been sissified by squeamish victorian ladies? Should we please them, and let the  common (therefore, coarse) majority of people go blithely to hell?

Or should we, at times, shock a few people into thinking? It was Jehovah God who commanded one of the prophets (Elijah?) to run around Jerusalem naked, and to marry a whore. This is shocking stuff, but it
is definitely necessary to shock people into thinking sometimes. I'm sure everybody was speculating about what that prophet would be up to next!

As a person who enjoys word origins and the evolution of language, it is my opinion that "common" words inevidatably become seen as "vulgar" over time, and it becomes necessary for prudish society to invent new "cute" terms for those "common" functions which are thought "coarse" or "vulgar". You find, for example, much "crude" language in Chaucer. While the stories may be "coarse" in Victorian terms, they are restrained and inoffensive when compared to any modern soap opera.

Let's de-sissify religion, so "real" men can worship God without blushing.

Which is not to say that we should all learn to cuss like sailors. If the bible is our example, then the highly euphemistic language is a guide to that fact that our speech should be decent and sensitive most of the time. For example, while the hypotheses advanced in this document may be somewhat shocking to some, the words used were generally the milder ones available from the various alternatives.

But to equate what is common and practical to what is vulgar and course is to deny the image of God in the common man. Jesus, as he hung exposed on a cursed cross, was not a handsome man, as most artists are prone to paint him. The bible tells us that there was nothing noble in his appearance. He was just one of us.

That's why that popular song is wrong, by the way. God IS one of us. And he didn't even get to ride the bus. But he was concerned with more than his own needs, he was concerned with our needs, gentry or commoner. But he often provoked the prudes by lowering himself to serve the common man.