Q: You may be wrong about the origin of “suffice it to say.” I believe it’s a mishearing of the more biblical sounding “it sufficeth to say.”
A: We’re sorry to disappoint you, but there’s no mishearing involved. Here’s the story.
The “eth” in “sufficeth” is, as you suggest, an archaic verb ending.
In the Old English and Middle English periods (which ended at around 1500), it was used as a suffix to form the third-person singular present indicative form of a verb.
For example, one would say that he or she or it “goeth,” “cometh,” “sendeth,” “walketh,” “sufficeth,” and so on.
Grammatically, the old “eth” form is parallel to the modern verb ending “s,” as in “goes,” “comes,” “sends,” “walks,” “suffices,” etc.
As we wrote in the blog entry you question, the expression “suffice it to say” is in the subjunctive mood. It did not arise from any confusion with the archaic verb ending “eth.”
So “it sufficeth to say” and “it suffices to say” are grammatically parallel (both in the indicative mood); one is archaic, that’s all.
Similarly, “sufficeth it to say” and “suffice it to say” are grammatically parallel (both in the subjunctive mood).
We hope this explanation sufficeth.
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