The Lord’s work in the last days is to come through the work of the unlearned. This is a theme that flows through the scriptures. For instance, the Doctrine and Covenants very specifically uses this imagery:
D&C 1:19
19 The weak things of the world shall come forth and break down the mighty and strong ones, that man should not counsel his fellow man, neither trust in the arm of flesh—
The weak things of the world becomes a reference to the Lord’s preference to bring about his marvelous work and a wonder through extraordinary means rather than through the paths of the politically or scholastically powerful. The Lord is reminding us that this is a work not of men, but of God, and the transformation of these “weak things” - these relatively unlearned and certainly un-powerful men - into representatives of God is part of the miracle - part of the marvelous work.
The process of alteration in these representatives yielded men who could no longer be described as “weak things.” The prophet Joseph Smith may have begun as a “weak” teenager of no social status, but he became the powerful leader of a people, and of a return to God. This is what Ether means:
Ether 12:27
27 And if men come unto me I will show unto them their weakness. I give unto men weakness that they may be humble; and my grace is sufficient for all men that humble themselves before me; for if they humble themselves before me, and have faith in me, then will I make weak things become strong unto them.
The Lord is not denigrating the idea of being learned, but is specifically contrasting the learning of the world with the power of the Spirit in the coming forth of the Book of Mormon The Book of Mormon is miraculous, and through the miracle of its existence, it can have the power to bring men to Christ. To understand the reason the Lord chose this mechanism over the bringing the Book of Mormon text to the world though the scholars can be seen in the case of the Dead Sea scrolls. While the discovery of the scrolls and the preservation of those which have been recovered might be considered miraculous, because both the discovery and the translation came through the learned of the world, the miraculous nature is little understood nor stressed.
The translation of the scrolls also comes through men, and not (directly) through the inspiration of God. Thus the scroll texts are embroiled in translation controversy with some seeing clear pointers to Jesus and others providing a completely different translation of the same passages. While the scrolls have no intent to teach of Christ they nevertheless could be a powerful witness for the passion of God’s people for Him. While they still evidence that devotion, they have no real power for bringing souls to God. They are texts from history, and the learned who have brought them forth necessarily remove the patina of miracle from them. So it would have been with the Book of Mormon. It is the very miraculous nature of the translation and delivery of he Book that provides its compelling power, above and beyond the words themselves.
Textual: Note that this verse presents a shift in both speaker and audience. Where the rest of the verses have been Nephi’s vision, this verse is very specifically placed in the mouth of God, and directed not at a general audience, but very specifically at the unlearned one who receives the “sealed book.”