Use the semicolon properly, always use it where it is appropriate; and never where it isn’t. Reserve the apostrophe for it’s proper use and omit it when its not needed.... Avoid commas, that are not necessary.... And don’t start a sentence with a conjunction.... If any word is improper at the end of a sentence, a linking verb is...

The passage is a comic catalogue of prescriptive “rules” of grammar and style, each immediately violated by the sentence that states it. The humor depends on readers recognizing the errors: a semicolon used clumsily, “it’s/its” mishandled, unnecessary commas inserted, a sentence begun with “And,” and the final clause ending with a linking verb (“is”). Read as satire, it pokes fun at pedantry and at the way rigid rule‑recitation can eclipse actual clarity and rhetorical effect. It also reflects Safire’s public persona as a language columnist who enjoyed exposing usage disputes and the ironies of “correctness.”