The printer’s manuscript has the noun poison instead of the expected adjective poisonous as the modifier for the noun serpents. The 1830 edition, on the other hand, has the expected poisonous. Elsewhere the text has only “poisonous serpents”:
There are no examples elsewhere in the Book of Mormon text (nor in the King James Bible) where the noun poison is used to modify a noun. Of course, one could argue that the 1830 typesetter emended poison to poisonous when he set the type. Yet even if 𝓞 had poison rather than poisonous, that could have been an error. Note that Oliver could have misheard “poisonous serpents” as “poison serpents” since poisonous ends in /ßs/ and the immediately following word, serpents, begins with an s.
We can find evidence in modern English for the phrase “poison serpents”, especially when the subject is biblical, as in these two examples from :
But this kind of usage seems particularly modern and inappropriate for the biblical style. Neither the Oxford English Dictionary nor Literature Online have any examples of “poison serpent(s)”.
Moreover, there isn’t much evidence from textual errors to help us analyze the variation here, although there is one example in 𝓞 of a mix-up between zeal and zealous:
In this case, Oliver Cowdery initially wrote the adjective zealous with its -ous ending rather than the noun zeal. He may have expected zealousness here but cut off writing the longer noun and crossed out the extra ous as soon as he realized his error.
Given that we have little evidence from transmissional probabilities in this instance, we will rely on internal evidence, namely, the preference everywhere else in the text for “poisonous serpents”. The critical text will therefore maintain the 1830 reading here in Mormon 8:24.
Summary: Maintain in Mormon 8:24 the expected “poisonous serpents” (the 1830 reading), not the anomalous “poison serpents” (the reading in 𝓟).