The sermon was too explicit - the words too explicit. I only got to the first part. The spiritual books say that purity and humility are two subjects that are delicate - to say too much or say the wrong thing is to wilt them, like a delicate flower. And yes, St. Paul says some things shouldn't even be mentioned. A word/phrase alluding to what the priest has in mind (and he'd better be right about the need of it) can be acceptable and effective -- but you don't wade whole hog into the subject with crass vocabulary that makes those trapped in the pew not just uncomfortable but perhaps vulnerable to impure thoughts or temptations, especially if it carries on and on.
We don't have sex ed classes for, among other things, reasons exactly along these lines. If one is modest, one is most careful about anything approaching the subject of purity - much less spewing broadside, rough words or expressions that one would not say if Our Lady was sitting there listening. But some of us go where angels would fear to tread. His approach/method, was out of place.