Apparently Oliver Cowdery did not expect the expression gushing out here, and so he initially wrote yielding up in 𝓟. After referring to the hearts of the people as being “swollen with joy”, perhaps Oliver expected a reference to the joy resulting from the people yielding themselves to God in humility, as in the following passage:
(I wish to thank Don Brugger for this reference.) Of course, it is very doubtful that this specific passage led to the momentary error here in 3 Nephi 4:33. More likely, four instances of “to yield up” earlier in 3 Nephi 3–4 prompted the initial error here in 𝓟:
In any event, Oliver caught his error here in 3 Nephi 4:33, correcting the up to out almost immediately and then somewhat later correcting yielding to gushing (the level of ink flow for the out is unchanged, but the ink flow for gushing is somewhat heavier). Since the 1830 edition also has gushing out, this must represent the reading of the original manuscript.
Except for an Isaiah quote in 1 Nephi 20:21 (“and the waters gushed out”), there is no other use of the verb gush in the Book of Mormon text. But interestingly, there is a passage in Jeremiah with phraseology much like 3 Nephi 4:33:
Summary: Despite the unusual use of gush in 3 Nephi 4:33, the original text undoubtedly read this way; the critical text will maintain gushing out, the 1830 reading and the corrected reading in 𝓟.